sysfs.c

   1 /*
   2  * sysfs - extract md related information from sysfs.  Part of:
   3  * mdadm - manage Linux "md" devices aka RAID arrays.
   4  *
   5  * Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
   6  *
   7  *
   8  *    This program is free software; you can redistribute it and/or modify
   9  *    it under the terms of the GNU General Public License as published by
  10  *    the Free Software Foundation; either version 2 of the License, or
  11  *    (at your option) any later version.
  12  *
  13  *    This program is distributed in the hope that it will be useful,
  14  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *    GNU General Public License for more details.
  17  *
  18  *    You should have received a copy of the GNU General Public License
  19  *    along with this program; if not, write to the Free Software
  20  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  *    Author: Neil Brown
  23  *    Email: <neilb@suse.de>
  24  */
  25
  26 #include        "mdadm.h"
  27 #include        <dirent.h>
  28 #include        <ctype.h>
  29 #include        "dlink.h"
  30
  31 #define MAX_SYSFS_PATH_LEN      120
  32
  33 struct dev_sysfs_rule {
  34         struct dev_sysfs_rule *next;
  35         char *devname;
  36         int uuid[4];
  37         int uuid_set;
  38         struct sysfs_entry {
  39                 struct sysfs_entry *next;
  40                 char *name;
  41                 char *value;
  42         } *entry;
  43 };
  44
  45 int load_sys(char *path, char *buf, int len)
  46 {
  47         int fd = open(path, O_RDONLY);
  48         int n;
  49         if (fd < 0)
  50                 return -1;
  51         n = read(fd, buf, len);
  52         close(fd);
  53         if (n <0 || n >= len)
  54                 return -1;
  55         buf[n] = 0;
  56         if (n && buf[n-1] == '\n')
  57                 buf[n-1] = 0;
  58         return 0;
  59 }
  60
  61 void sysfs_free(struct mdinfo *sra)
  62 {
  63         while (sra) {
  64                 struct mdinfo *sra2 = sra->next;
  65                 while (sra->devs) {
  66                         struct mdinfo *d = sra->devs;
  67                         sra->devs = d->next;
  68                         free(d->bb.entries);
  69                         free(d);
  70                 }
  71                 free(sra->bb.entries);
  72                 free(sra);
  73                 sra = sra2;
  74         }
  75 }
  76
  77 int sysfs_open(char *devnm, char *devname, char *attr)
  78 {
  79         char fname[MAX_SYSFS_PATH_LEN];
  80         int fd;
  81
  82         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/", devnm);
  83         if (devname) {
  84                 strncat(fname, devname, MAX_SYSFS_PATH_LEN - strlen(fname));
  85                 strncat(fname, "/", MAX_SYSFS_PATH_LEN - strlen(fname));
  86         }
  87         strncat(fname, attr, MAX_SYSFS_PATH_LEN - strlen(fname));
  88         fd = open(fname, O_RDWR);
  89         if (fd < 0 && errno == EACCES)
  90                 fd = open(fname, O_RDONLY);
  91         return fd;
  92 }
  93
  94 void sysfs_init_dev(struct mdinfo *mdi, dev_t devid)
  95 {
  96         snprintf(mdi->sys_name,
  97                  sizeof(mdi->sys_name), "dev-%s", devid2kname(devid));
  98 }
  99
 100 int sysfs_init(struct mdinfo *mdi, int fd, char *devnm)
 101 {
 102         struct stat stb;
 103         char fname[MAX_SYSFS_PATH_LEN];
 104         int retval = -ENODEV;
 105
 106         mdi->sys_name[0] = 0;
 107         if (fd >= 0)
 108                 devnm = fd2devnm(fd);
 109
 110         if (devnm == NULL)
 111                 goto out;
 112
 113         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md", devnm);
 114
 115         if (stat(fname, &stb))
 116                 goto out;
 117         if (!S_ISDIR(stb.st_mode))
 118                 goto out;
 119         strcpy(mdi->sys_name, devnm);
 120
 121         retval = 0;
 122 out:
 123         return retval;
 124 }
 125
 126 struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options)
 127 {
 128         char fname[PATH_MAX];
 129         char buf[PATH_MAX];
 130         char *base;
 131         char *dbase;
 132         struct mdinfo *sra;
 133         struct mdinfo *dev, **devp;
 134         DIR *dir = NULL;
 135         struct dirent *de;
 136
 137         sra = xcalloc(1, sizeof(*sra));
 138         if (sysfs_init(sra, fd, devnm)) {
 139                 free(sra);
 140                 return NULL;
 141         }
 142
 143         sprintf(fname, "/sys/block/%s/md/", sra->sys_name);
 144         base = fname + strlen(fname);
 145
 146         sra->devs = NULL;
 147         if (options & GET_VERSION) {
 148                 strcpy(base, "metadata_version");
 149                 if (load_sys(fname, buf, sizeof(buf)))
 150                         goto abort;
 151                 if (strncmp(buf, "none", 4) == 0) {
 152                         sra->array.major_version =
 153                                 sra->array.minor_version = -1;
 154                         strcpy(sra->text_version, "");
 155                 } else if (strncmp(buf, "external:", 9) == 0) {
 156                         sra->array.major_version = -1;
 157                         sra->array.minor_version = -2;
 158                         strcpy(sra->text_version, buf+9);
 159                 } else {
 160                         sscanf(buf, "%d.%d",
 161                                &sra->array.major_version,
 162                                &sra->array.minor_version);
 163                         strcpy(sra->text_version, buf);
 164                 }
 165         }
 166         if (options & GET_LEVEL) {
 167                 strcpy(base, "level");
 168                 if (load_sys(fname, buf, sizeof(buf)))
 169                         goto abort;
 170                 sra->array.level = map_name(pers, buf);
 171         }
 172         if (options & GET_LAYOUT) {
 173                 strcpy(base, "layout");
 174                 if (load_sys(fname, buf, sizeof(buf)))
 175                         goto abort;
 176                 sra->array.layout = strtoul(buf, NULL, 0);
 177         }
 178         if (options & (GET_DISKS|GET_STATE)) {
 179                 strcpy(base, "raid_disks");
 180                 if (load_sys(fname, buf, sizeof(buf)))
 181                         goto abort;
 182                 sra->array.raid_disks = strtoul(buf, NULL, 0);
 183         }
 184         if (options & GET_COMPONENT) {
 185                 strcpy(base, "component_size");
 186                 if (load_sys(fname, buf, sizeof(buf)))
 187                         goto abort;
 188                 sra->component_size = strtoull(buf, NULL, 0);
 189                 /* sysfs reports "K", but we want sectors */
 190                 sra->component_size *= 2;
 191         }
 192         if (options & GET_CHUNK) {
 193                 strcpy(base, "chunk_size");
 194                 if (load_sys(fname, buf, sizeof(buf)))
 195                         goto abort;
 196                 sra->array.chunk_size = strtoul(buf, NULL, 0);
 197         }
 198         if (options & GET_CACHE) {
 199                 strcpy(base, "stripe_cache_size");
 200                 if (load_sys(fname, buf, sizeof(buf)))
 201                         /* Probably level doesn't support it */
 202                         sra->cache_size = 0;
 203                 else
 204                         sra->cache_size = strtoul(buf, NULL, 0);
 205         }
 206         if (options & GET_MISMATCH) {
 207                 strcpy(base, "mismatch_cnt");
 208                 if (load_sys(fname, buf, sizeof(buf)))
 209                         goto abort;
 210                 sra->mismatch_cnt = strtoul(buf, NULL, 0);
 211         }
 212         if (options & GET_SAFEMODE) {
 213                 int scale = 1;
 214                 int dot = 0;
 215                 unsigned i;
 216                 unsigned long msec;
 217                 size_t len;
 218
 219                 strcpy(base, "safe_mode_delay");
 220                 if (load_sys(fname, buf, sizeof(buf)))
 221                         goto abort;
 222
 223                 /* remove a period, and count digits after it */
 224                 len = strlen(buf);
 225                 for (i = 0; i < len; i++) {
 226                         if (dot) {
 227                                 if (isdigit(buf[i])) {
 228                                         buf[i-1] = buf[i];
 229                                         scale *= 10;
 230                                 }
 231                                 buf[i] = 0;
 232                         } else if (buf[i] == '.') {
 233                                 dot=1;
 234                                 buf[i] = 0;
 235                         }
 236                 }
 237                 msec = strtoul(buf, NULL, 10);
 238                 msec = (msec * 1000) / scale;
 239                 sra->safe_mode_delay = msec;
 240         }
 241         if (options & GET_BITMAP_LOCATION) {
 242                 strcpy(base, "bitmap/location");
 243                 if (load_sys(fname, buf, sizeof(buf)))
 244                         goto abort;
 245                 if (strncmp(buf, "file", 4) == 0)
 246                         sra->bitmap_offset = 1;
 247                 else if (strncmp(buf, "none", 4) == 0)
 248                         sra->bitmap_offset = 0;
 249                 else if (buf[0] == '+')
 250                         sra->bitmap_offset = strtol(buf+1, NULL, 10);
 251                 else
 252                         goto abort;
 253         }
 254
 255         if (options & GET_ARRAY_STATE) {
 256                 strcpy(base, "array_state");
 257                 if (load_sys(fname, buf, sizeof(buf)))
 258                         goto abort;
 259                 sra->array_state = map_name(sysfs_array_states, buf);
 260         }
 261
 262         if (options & GET_CONSISTENCY_POLICY) {
 263                 strcpy(base, "consistency_policy");
 264                 if (load_sys(fname, buf, sizeof(buf)))
 265                         sra->consistency_policy = CONSISTENCY_POLICY_UNKNOWN;
 266                 else
 267                         sra->consistency_policy = map_name(consistency_policies,
 268                                                            buf);
 269         }
 270
 271         if (! (options & GET_DEVS))
 272                 return sra;
 273
 274         /* Get all the devices as well */
 275         *base = 0;
 276         dir = opendir(fname);
 277         if (!dir)
 278                 goto abort;
 279         sra->array.spare_disks = 0;
 280         sra->array.active_disks = 0;
 281         sra->array.failed_disks = 0;
 282         sra->array.working_disks = 0;
 283
 284         devp = &sra->devs;
 285         sra->devs = NULL;
 286         while ((de = readdir(dir)) != NULL) {
 287                 char *ep;
 288                 if (de->d_ino == 0 ||
 289                     strncmp(de->d_name, "dev-", 4) != 0)
 290                         continue;
 291                 strcpy(base, de->d_name);
 292                 dbase = base + strlen(base);
 293                 *dbase++ = '/';
 294
 295                 dev = xcalloc(1, sizeof(*dev));
 296
 297                 /* Always get slot, major, minor */
 298                 strcpy(dbase, "slot");
 299                 if (load_sys(fname, buf, sizeof(buf))) {
 300                         /* hmm... unable to read 'slot' maybe the device
 301                          * is going away?
 302                          */
 303                         strcpy(dbase, "block");
 304                         if (readlink(fname, buf, sizeof(buf)) < 0 &&
 305                             errno != ENAMETOOLONG) {
 306                                 /* ...yup device is gone */
 307                                 free(dev);
 308                                 continue;
 309                         } else {
 310                                 /* slot is unreadable but 'block' link
 311                                  * still intact... something bad is happening
 312                                  * so abort
 313                                  */
 314                                 free(dev);
 315                                 goto abort;
 316                         }
 317
 318                 }
 319                 strcpy(dev->sys_name, de->d_name);
 320                 dev->disk.raid_disk = strtoul(buf, &ep, 10);
 321                 if (*ep) dev->disk.raid_disk = -1;
 322
 323                 sra->array.nr_disks++;
 324                 strcpy(dbase, "block/dev");
 325                 if (load_sys(fname, buf, sizeof(buf))) {
 326                         /* assume this is a stale reference to a hot
 327                          * removed device
 328                          */
 329                         if (!(options & GET_DEVS_ALL)) {
 330                                 free(dev);
 331                                 continue;
 332                         }
 333                 } else {
 334                         sscanf(buf, "%d:%d", &dev->disk.major, &dev->disk.minor);
 335                 }
 336
 337                 if (!(options & GET_DEVS_ALL)) {
 338                         /* special case check for block devices that can go 'offline' */
 339                         strcpy(dbase, "block/device/state");
 340                         if (load_sys(fname, buf, sizeof(buf)) == 0 &&
 341                             strncmp(buf, "offline", 7) == 0) {
 342                                 free(dev);
 343                                 continue;
 344                         }
 345                 }
 346
 347                 /* finally add this disk to the array */
 348                 *devp = dev;
 349                 devp = & dev->next;
 350                 dev->next = NULL;
 351
 352                 if (options & GET_OFFSET) {
 353                         strcpy(dbase, "offset");
 354                         if (load_sys(fname, buf, sizeof(buf)))
 355                                 goto abort;
 356                         dev->data_offset = strtoull(buf, NULL, 0);
 357                         strcpy(dbase, "new_offset");
 358                         if (load_sys(fname, buf, sizeof(buf)) == 0)
 359                                 dev->new_data_offset = strtoull(buf, NULL, 0);
 360                         else
 361                                 dev->new_data_offset = dev->data_offset;
 362                 }
 363                 if (options & GET_SIZE) {
 364                         strcpy(dbase, "size");
 365                         if (load_sys(fname, buf, sizeof(buf)))
 366                                 goto abort;
 367                         dev->component_size = strtoull(buf, NULL, 0) * 2;
 368                 }
 369                 if (options & GET_STATE) {
 370                         dev->disk.state = 0;
 371                         strcpy(dbase, "state");
 372                         if (load_sys(fname, buf, sizeof(buf)))
 373                                 goto abort;
 374                         if (strstr(buf, "faulty"))
 375                                 dev->disk.state |= (1<<MD_DISK_FAULTY);
 376                         else {
 377                                 sra->array.working_disks++;
 378                                 if (strstr(buf, "in_sync")) {
 379                                         dev->disk.state |= (1<<MD_DISK_SYNC);
 380                                         sra->array.active_disks++;
 381                                 }
 382                                 if (dev->disk.state == 0)
 383                                         sra->array.spare_disks++;
 384                         }
 385                 }
 386                 if (options & GET_ERROR) {
 387                         strcpy(buf, "errors");
 388                         if (load_sys(fname, buf, sizeof(buf)))
 389                                 goto abort;
 390                         dev->errors = strtoul(buf, NULL, 0);
 391                 }
 392         }
 393
 394         if ((options & GET_STATE) && sra->array.raid_disks)
 395                 sra->array.failed_disks = sra->array.raid_disks -
 396                         sra->array.active_disks - sra->array.spare_disks;
 397
 398         closedir(dir);
 399         return sra;
 400
 401  abort:
 402         if (dir)
 403                 closedir(dir);
 404         sysfs_free(sra);
 405         return NULL;
 406 }
 407
 408 int sysfs_attr_match(const char *attr, const char *str)
 409 {
 410         /* See if attr, read from a sysfs file, matches
 411          * str.  They must either be the same, or attr can
 412          * have a trailing newline or comma
 413          */
 414         while (*attr && *str && *attr == *str) {
 415                 attr++;
 416                 str++;
 417         }
 418
 419         if (*str || (*attr && *attr != ',' && *attr != '\n'))
 420                 return 0;
 421         return 1;
 422 }
 423
 424 int sysfs_match_word(const char *word, char **list)
 425 {
 426         int n;
 427         for (n=0; list[n]; n++)
 428                 if (sysfs_attr_match(word, list[n]))
 429                         break;
 430         return n;
 431 }
 432
 433 unsigned long long get_component_size(int fd)
 434 {
 435         /* Find out the component size of the array.
 436          * We cannot trust GET_ARRAY_INFO ioctl as it's
 437          * size field is only 32bits.
 438          * So look in /sys/block/mdXXX/md/component_size
 439          *
 440          * This returns in units of sectors.
 441          */
 442         struct stat stb;
 443         char fname[MAX_SYSFS_PATH_LEN];
 444         int n;
 445         if (fstat(fd, &stb))
 446                 return 0;
 447         snprintf(fname, MAX_SYSFS_PATH_LEN,
 448                  "/sys/block/%s/md/component_size", stat2devnm(&stb));
 449         fd = open(fname, O_RDONLY);
 450         if (fd < 0)
 451                 return 0;
 452         n = read(fd, fname, sizeof(fname));
 453         close(fd);
 454         if (n < 0 || n == sizeof(fname))
 455                 return 0;
 456         fname[n] = 0;
 457         return strtoull(fname, NULL, 10) * 2;
 458 }
 459
 460 int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
 461                   char *name, char *val)
 462 {
 463         char fname[MAX_SYSFS_PATH_LEN];
 464         unsigned int n;
 465         int fd;
 466
 467         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
 468                 sra->sys_name, dev?dev->sys_name:"", name);
 469         fd = open(fname, O_WRONLY);
 470         if (fd < 0)
 471                 return -1;
 472         n = write(fd, val, strlen(val));
 473         close(fd);
 474         if (n != strlen(val)) {
 475                 dprintf("failed to write '%s' to '%s' (%s)\n",
 476                         val, fname, strerror(errno));
 477                 return -1;
 478         }
 479         return 0;
 480 }
 481
 482 int sysfs_set_num(struct mdinfo *sra, struct mdinfo *dev,
 483                   char *name, unsigned long long val)
 484 {
 485         char valstr[50];
 486         sprintf(valstr, "%llu", val);
 487         return sysfs_set_str(sra, dev, name, valstr);
 488 }
 489
 490 int sysfs_set_num_signed(struct mdinfo *sra, struct mdinfo *dev,
 491                          char *name, long long val)
 492 {
 493         char valstr[50];
 494         sprintf(valstr, "%lli", val);
 495         return sysfs_set_str(sra, dev, name, valstr);
 496 }
 497
 498 int sysfs_uevent(struct mdinfo *sra, char *event)
 499 {
 500         char fname[MAX_SYSFS_PATH_LEN];
 501         int n;
 502         int fd;
 503
 504         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/uevent",
 505                 sra->sys_name);
 506         fd = open(fname, O_WRONLY);
 507         if (fd < 0)
 508                 return -1;
 509         n = write(fd, event, strlen(event));
 510         close(fd);
 511         if (n != (int)strlen(event)) {
 512                 dprintf("failed to write '%s' to '%s' (%s)\n",
 513                         event, fname, strerror(errno));
 514                 return -1;
 515         }
 516         return 0;
 517 }
 518
 519 int sysfs_attribute_available(struct mdinfo *sra, struct mdinfo *dev, char *name)
 520 {
 521         char fname[MAX_SYSFS_PATH_LEN];
 522         struct stat st;
 523
 524         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
 525                 sra->sys_name, dev?dev->sys_name:"", name);
 526
 527         return stat(fname, &st) == 0;
 528 }
 529
 530 int sysfs_get_fd(struct mdinfo *sra, struct mdinfo *dev,
 531                        char *name)
 532 {
 533         char fname[MAX_SYSFS_PATH_LEN];
 534         int fd;
 535
 536         snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/%s/%s",
 537                 sra->sys_name, dev?dev->sys_name:"", name);
 538         fd = open(fname, O_RDWR);
 539         if (fd < 0)
 540                 fd = open(fname, O_RDONLY);
 541         return fd;
 542 }
 543
 544 int sysfs_fd_get_ll(int fd, unsigned long long *val)
 545 {
 546         char buf[50];
 547         int n;
 548         char *ep;
 549
 550         lseek(fd, 0, 0);
 551         n = read(fd, buf, sizeof(buf));
 552         if (n <= 0 || n == sizeof(buf))
 553                 return -2;
 554         buf[n] = 0;
 555         *val = strtoull(buf, &ep, 0);
 556         if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
 557                 return -1;
 558         return 0;
 559 }
 560
 561 int sysfs_get_ll(struct mdinfo *sra, struct mdinfo *dev,
 562                        char *name, unsigned long long *val)
 563 {
 564         int n;
 565         int fd;
 566
 567         fd = sysfs_get_fd(sra, dev, name);
 568         if (fd < 0)
 569                 return -1;
 570         n = sysfs_fd_get_ll(fd, val);
 571         close(fd);
 572         return n;
 573 }
 574
 575 int sysfs_fd_get_two(int fd, unsigned long long *v1, unsigned long long *v2)
 576 {
 577         /* two numbers in this sysfs file, either
 578          *  NNN (NNN)
 579          * or
 580          *  NNN / NNN
 581          */
 582         char buf[80];
 583         int n;
 584         char *ep, *ep2;
 585
 586         lseek(fd, 0, 0);
 587         n = read(fd, buf, sizeof(buf));
 588         if (n <= 0 || n == sizeof(buf))
 589                 return -2;
 590         buf[n] = 0;
 591         *v1 = strtoull(buf, &ep, 0);
 592         if (ep == buf || (*ep != 0 && *ep != '\n' && *ep != ' '))
 593                 return -1;
 594         while (*ep == ' ' || *ep == '/' || *ep == '(')
 595                 ep++;
 596         *v2 = strtoull(ep, &ep2, 0);
 597         if (ep2 == ep || (*ep2 != 0 && *ep2 != '\n' && *ep2 != ' ' && *ep2 != ')')) {
 598                 *v2 = *v1;
 599                 return 1;
 600         }
 601         return 2;
 602 }
 603
 604 int sysfs_get_two(struct mdinfo *sra, struct mdinfo *dev,
 605                   char *name, unsigned long long *v1, unsigned long long *v2)
 606 {
 607         int n;
 608         int fd;
 609
 610         fd = sysfs_get_fd(sra, dev, name);
 611         if (fd < 0)
 612                 return -1;
 613         n = sysfs_fd_get_two(fd, v1, v2);
 614         close(fd);
 615         return n;
 616 }
 617
 618 int sysfs_fd_get_str(int fd, char *val, int size)
 619 {
 620         int n;
 621
 622         lseek(fd, 0, 0);
 623         n = read(fd, val, size);
 624         if (n <= 0 || n == size)
 625                 return -1;
 626         val[n] = 0;
 627         return n;
 628 }
 629
 630 int sysfs_get_str(struct mdinfo *sra, struct mdinfo *dev,
 631                        char *name, char *val, int size)
 632 {
 633         int n;
 634         int fd;
 635
 636         fd = sysfs_get_fd(sra, dev, name);
 637         if (fd < 0)
 638                 return -1;
 639         n = sysfs_fd_get_str(fd, val, size);
 640         close(fd);
 641         return n;
 642 }
 643
 644 int sysfs_set_safemode(struct mdinfo *sra, unsigned long ms)
 645 {
 646         unsigned long sec;
 647         unsigned long msec;
 648         char delay[30];
 649
 650         sec = ms / 1000;
 651         msec = ms % 1000;
 652
 653         sprintf(delay, "%ld.%03ld\n", sec, msec);
 654         /*             this '\n' ^ needed for kernels older than 2.6.28 */
 655         return sysfs_set_str(sra, NULL, "safe_mode_delay", delay);
 656 }
 657
 658 int sysfs_set_array(struct mdinfo *info, int vers)
 659 {
 660         int rv = 0;
 661         char ver[100];
 662         int raid_disks = info->array.raid_disks;
 663
 664         ver[0] = 0;
 665         if (info->array.major_version == -1 &&
 666             info->array.minor_version == -2) {
 667                 char buf[1024];
 668
 669                 strcat(strcpy(ver, "external:"), info->text_version);
 670
 671                 /* meta version might already be set if we are setting
 672                  * new geometry for a reshape.  In that case we don't
 673                  * want to over-write the 'readonly' flag that is
 674                  * stored in the metadata version.  So read the current
 675                  * version first, and preserve the flag
 676                  */
 677                 if (sysfs_get_str(info, NULL, "metadata_version",
 678                                   buf, 1024) > 0)
 679                         if (strlen(buf) >= 9 && buf[9] == '-')
 680                                 ver[9] = '-';
 681
 682                 if ((vers % 100) < 2 ||
 683                     sysfs_set_str(info, NULL, "metadata_version",
 684                                   ver) < 0) {
 685                         pr_err("This kernel does not support external metadata.\n");
 686                         return 1;
 687                 }
 688         }
 689         if (info->array.level < 0)
 690                 return 0; /* FIXME */
 691         rv |= sysfs_set_str(info, NULL, "level",
 692                             map_num(pers, info->array.level));
 693         if (info->reshape_active && info->delta_disks != UnSet)
 694                 raid_disks -= info->delta_disks;
 695         rv |= sysfs_set_num(info, NULL, "raid_disks", raid_disks);
 696         rv |= sysfs_set_num(info, NULL, "chunk_size", info->array.chunk_size);
 697         rv |= sysfs_set_num(info, NULL, "layout", info->array.layout);
 698         rv |= sysfs_set_num(info, NULL, "component_size", info->component_size/2);
 699         if (info->custom_array_size) {
 700                 int rc;
 701
 702                 rc = sysfs_set_num(info, NULL, "array_size",
 703                                    info->custom_array_size/2);
 704                 if (rc && errno == ENOENT) {
 705                         pr_err("This kernel does not have the md/array_size attribute, the array may be larger than expected\n");
 706                         rc = 0;
 707                 }
 708                 rv |= rc;
 709         }
 710
 711         if (info->array.level > 0)
 712                 rv |= sysfs_set_num(info, NULL, "resync_start", info->resync_start);
 713
 714         if (info->reshape_active) {
 715                 rv |= sysfs_set_num(info, NULL, "reshape_position",
 716                                     info->reshape_progress);
 717                 rv |= sysfs_set_num(info, NULL, "chunk_size", info->new_chunk);
 718                 rv |= sysfs_set_num(info, NULL, "layout", info->new_layout);
 719                 rv |= sysfs_set_num(info, NULL, "raid_disks",
 720                                     info->array.raid_disks);
 721                 /* We don't set 'new_level' here.  That can only happen
 722                  * once the reshape completes.
 723                  */
 724         }
 725
 726         if (info->consistency_policy == CONSISTENCY_POLICY_PPL) {
 727                 if (sysfs_set_str(info, NULL, "consistency_policy",
 728                                   map_num(consistency_policies,
 729                                           info->consistency_policy))) {
 730                         pr_err("This kernel does not support PPL. Falling back to consistency-policy=resync.\n");
 731                         info->consistency_policy = CONSISTENCY_POLICY_RESYNC;
 732                 }
 733         }
 734
 735         return rv;
 736 }
 737
 738 int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume)
 739 {
 740         char dv[PATH_MAX];
 741         char nm[PATH_MAX];
 742         char *dname;
 743         int rv;
 744         int i;
 745
 746         sprintf(dv, "%d:%d", sd->disk.major, sd->disk.minor);
 747         rv = sysfs_set_str(sra, NULL, "new_dev", dv);
 748         if (rv)
 749                 return rv;
 750
 751         memset(nm, 0, sizeof(nm));
 752         dname = devid2kname(makedev(sd->disk.major, sd->disk.minor));
 753         strcpy(sd->sys_name, "dev-");
 754         strcpy(sd->sys_name+4, dname);
 755
 756         /* test write to see if 'recovery_start' is available */
 757         if (resume && sd->recovery_start < MaxSector &&
 758             sysfs_set_num(sra, sd, "recovery_start", 0)) {
 759                 sysfs_set_str(sra, sd, "state", "remove");
 760                 return -1;
 761         }
 762
 763         rv = sysfs_set_num(sra, sd, "offset", sd->data_offset);
 764         rv |= sysfs_set_num(sra, sd, "size", (sd->component_size+1) / 2);
 765         if (sra->array.level != LEVEL_CONTAINER) {
 766                 if (sra->consistency_policy == CONSISTENCY_POLICY_PPL) {
 767                         rv |= sysfs_set_num(sra, sd, "ppl_sector", sd->ppl_sector);
 768                         rv |= sysfs_set_num(sra, sd, "ppl_size", sd->ppl_size);
 769                 }
 770                 if (sd->recovery_start == MaxSector)
 771                         /* This can correctly fail if array isn't started,
 772                          * yet, so just ignore status for now.
 773                          */
 774                         sysfs_set_str(sra, sd, "state", "insync");
 775                 if (sd->disk.raid_disk >= 0)
 776                         rv |= sysfs_set_num(sra, sd, "slot", sd->disk.raid_disk);
 777                 if (resume)
 778                         sysfs_set_num(sra, sd, "recovery_start", sd->recovery_start);
 779         }
 780         if (sd->bb.supported) {
 781                 if (sysfs_set_str(sra, sd, "state", "external_bbl")) {
 782                         /*
 783                          * backward compatibility - if kernel doesn't support
 784                          * bad blocks for external metadata, let it continue
 785                          * as long as there are none known so far
 786                          */
 787                         if (sd->bb.count) {
 788                                 pr_err("The kernel has no support for bad blocks in external metadata\n");
 789                                 return -1;
 790                         }
 791                 }
 792
 793                 for (i = 0; i < sd->bb.count; i++) {
 794                         char s[30];
 795                         const struct md_bb_entry *entry = &sd->bb.entries[i];
 796
 797                         snprintf(s, sizeof(s) - 1, "%llu %d\n", entry->sector,
 798                                  entry->length);
 799                         rv |= sysfs_set_str(sra, sd, "bad_blocks", s);
 800                 }
 801         }
 802         return rv;
 803 }
 804
 805 #if 0
 806 int sysfs_disk_to_sg(int fd)
 807 {
 808         /* from an open block device, try find and open its corresponding
 809          * scsi_generic interface
 810          */
 811         struct stat st;
 812         char path[256];
 813         char sg_path[256];
 814         char sg_major_minor[10];
 815         char *c;
 816         DIR *dir;
 817         struct dirent *de;
 818         int major, minor, rv;
 819
 820         if (fstat(fd, &st))
 821                 return -1;
 822
 823         snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device",
 824                  major(st.st_rdev), minor(st.st_rdev));
 825
 826         dir = opendir(path);
 827         if (!dir)
 828                 return -1;
 829
 830         de = readdir(dir);
 831         while (de) {
 832                 if (strncmp("scsi_generic:", de->d_name,
 833                             strlen("scsi_generic:")) == 0)
 834                         break;
 835                 de = readdir(dir);
 836         }
 837         closedir(dir);
 838
 839         if (!de)
 840                 return -1;
 841
 842         snprintf(sg_path, sizeof(sg_path), "%s/%s/dev", path, de->d_name);
 843         fd = open(sg_path, O_RDONLY);
 844         if (fd < 0)
 845                 return fd;
 846
 847         rv = read(fd, sg_major_minor, sizeof(sg_major_minor));
 848         close(fd);
 849         if (rv < 0 || rv == sizeof(sg_major_minor))
 850                 return -1;
 851         else
 852                 sg_major_minor[rv - 1] = '\0';
 853
 854         c = strchr(sg_major_minor, ':');
 855         *c = '\0';
 856         c++;
 857         major = strtol(sg_major_minor, NULL, 10);
 858         minor = strtol(c, NULL, 10);
 859         snprintf(path, sizeof(path), "/dev/.tmp.md.%d:%d:%d",
 860                  (int) getpid(), major, minor);
 861         if (mknod(path, S_IFCHR|0600, makedev(major, minor))==0) {
 862                         fd = open(path, O_RDONLY);
 863                         unlink(path);
 864                         return fd;
 865         }
 866
 867         return -1;
 868 }
 869 #endif
 870
 871 int sysfs_disk_to_scsi_id(int fd, __u32 *id)
 872 {
 873         /* from an open block device, try to retrieve it scsi_id */
 874         struct stat st;
 875         char path[256];
 876         DIR *dir;
 877         struct dirent *de;
 878         int host, bus, target, lun;
 879
 880         if (fstat(fd, &st))
 881                 return 1;
 882
 883         snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/device/scsi_device",
 884                  major(st.st_rdev), minor(st.st_rdev));
 885
 886         dir = opendir(path);
 887         if (!dir)
 888                 return 1;
 889
 890         for (de = readdir(dir); de; de = readdir(dir)) {
 891                 int count;
 892
 893                 if (de->d_type != DT_DIR)
 894                         continue;
 895
 896                 count = sscanf(de->d_name, "%d:%d:%d:%d", &host, &bus, &target, &lun);
 897                 if (count == 4)
 898                         break;
 899         }
 900         closedir(dir);
 901
 902         if (!de)
 903                 return 1;
 904
 905         *id = (host << 24) | (bus << 16) | (target << 8) | (lun << 0);
 906         return 0;
 907 }
 908
 909 int sysfs_unique_holder(char *devnm, long rdev)
 910 {
 911         /* Check that devnm is a holder of rdev,
 912          * and is the only holder.
 913          * we should be locked against races by
 914          * an O_EXCL on devnm
 915          * Return values:
 916          *  0 - not unique, not even a holder
 917          *  1 - unique, this is the only holder.
 918          *  2/3 - not unique, there is another holder
 919          * -1 - error, cannot find the holders
 920          */
 921         DIR *dir;
 922         struct dirent *de;
 923         char dirname[100];
 924         char l;
 925         int ret = 0;
 926         sprintf(dirname, "/sys/dev/block/%d:%d/holders",
 927                 major(rdev), minor(rdev));
 928         dir = opendir(dirname);
 929         if (!dir)
 930                 return -1;
 931         l = strlen(dirname);
 932         while ((de = readdir(dir)) != NULL) {
 933                 char buf[100];
 934                 char *sl;
 935                 int n;
 936
 937                 if (de->d_ino == 0)
 938                         continue;
 939                 if (de->d_name[0] == '.')
 940                         continue;
 941                 strcpy(dirname+l, "/");
 942                 strcat(dirname+l, de->d_name);
 943                 n = readlink(dirname, buf, sizeof(buf)-1);
 944                 if (n <= 0)
 945                         continue;
 946                 buf[n] = 0;
 947                 sl = strrchr(buf, '/');
 948                 if (!sl)
 949                         continue;
 950                 sl++;
 951
 952                 if (strcmp(devnm, sl) == 0)
 953                         ret |= 1;
 954                 else
 955                         ret |= 2;
 956         }
 957         closedir(dir);
 958         return ret;
 959 }
 960
 961 int sysfs_freeze_array(struct mdinfo *sra)
 962 {
 963         /* Try to freeze resync/rebuild on this array/container.
 964          * Return -1 if the array is busy,
 965          * return 0 if this kernel doesn't support 'frozen'
 966          * return 1 if it worked.
 967          */
 968         char buf[20];
 969
 970         if (!sysfs_attribute_available(sra, NULL, "sync_action"))
 971                 return 1; /* no sync_action == frozen */
 972         if (sysfs_get_str(sra, NULL, "sync_action", buf, 20) <= 0)
 973                 return 0;
 974         if (strcmp(buf, "frozen\n") == 0)
 975                 /* Already frozen */
 976                 return 0;
 977         if (strcmp(buf, "idle\n") != 0 && strcmp(buf, "recover\n") != 0)
 978                 return -1;
 979         if (sysfs_set_str(sra, NULL, "sync_action", "frozen") < 0)
 980                 return 0;
 981         return 1;
 982 }
 983
 984 int sysfs_wait(int fd, int *msec)
 985 {
 986         /* Wait up to '*msec' for fd to have an exception condition.
 987          * if msec == NULL, wait indefinitely.
 988          */
 989         fd_set fds;
 990         int n;
 991         FD_ZERO(&fds);
 992         FD_SET(fd, &fds);
 993         if (msec == NULL)
 994                 n = select(fd+1, NULL, NULL, &fds, NULL);
 995         else if (*msec < 0)
 996                 n = 0;
 997         else {
 998                 struct timeval start, end, tv;
 999                 gettimeofday(&start, NULL);
1000                 if (*msec < 1000) {
1001                         tv.tv_sec = 0;
1002                         tv.tv_usec = (*msec)*1000;
1003                 } else {
1004                         tv.tv_sec = (*msec)/1000;
1005                         tv.tv_usec = 0;
1006                 }
1007                 n = select(fd+1, NULL, NULL, &fds, &tv);
1008                 gettimeofday(&end, NULL);
1009                 end.tv_sec -= start.tv_sec;
1010                 *msec -= (end.tv_sec * 1000 + end.tv_usec/1000
1011                           - start.tv_usec/1000) + 1;
1012         }
1013         return n;
1014 }
1015
1016 int sysfs_rules_apply_check(const struct mdinfo *sra,
1017                             const struct sysfs_entry *ent)
1018 {
1019         /* Check whether parameter is regular file,
1020          * exists and is under specified directory.
1021          */
1022         char fname[MAX_SYSFS_PATH_LEN];
1023         char dname[MAX_SYSFS_PATH_LEN];
1024         char resolved_path[PATH_MAX];
1025         char resolved_dir[PATH_MAX];
1026
1027         if (sra == NULL || ent == NULL)
1028                 return -1;
1029
1030         snprintf(dname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md/", sra->sys_name);
1031         snprintf(fname, MAX_SYSFS_PATH_LEN, "%s/%s", dname, ent->name);
1032
1033         if (realpath(fname, resolved_path) == NULL ||
1034             realpath(dname, resolved_dir) == NULL)
1035                 return -1;
1036
1037         if (strncmp(resolved_dir, resolved_path,
1038                     strnlen(resolved_dir, PATH_MAX)) != 0)
1039                 return -1;
1040
1041         return 0;
1042 }
1043
1044 static struct dev_sysfs_rule *sysfs_rules;
1045
1046 void sysfs_rules_apply(char *devnm, struct mdinfo *dev)
1047 {
1048         struct dev_sysfs_rule *rules = sysfs_rules;
1049
1050         while (rules) {
1051                 struct sysfs_entry *ent = rules->entry;
1052                 int match  = 0;
1053
1054                 if (!rules->uuid_set) {
1055                         if (rules->devname)
1056                                 match = strcmp(devnm, rules->devname) == 0;
1057                 } else {
1058                         match = memcmp(dev->uuid, rules->uuid,
1059                                        sizeof(int[4])) == 0;
1060                 }
1061
1062                 while (match && ent) {
1063                         if (sysfs_rules_apply_check(dev, ent) < 0)
1064                                 pr_err("SYSFS: failed to write '%s' to '%s'\n",
1065                                         ent->value, ent->name);
1066                         else
1067                                 sysfs_set_str(dev, NULL, ent->name, ent->value);
1068                         ent = ent->next;
1069                 }
1070                 rules = rules->next;
1071         }
1072 }
1073
1074 static void sysfs_rule_free(struct dev_sysfs_rule *rule)
1075 {
1076         struct sysfs_entry *entry;
1077
1078         while (rule) {
1079                 struct dev_sysfs_rule *tmp = rule->next;
1080
1081                 entry = rule->entry;
1082                 while (entry) {
1083                         struct sysfs_entry *tmp = entry->next;
1084
1085                         free(entry->name);
1086                         free(entry->value);
1087                         free(entry);
1088                         entry = tmp;
1089                 }
1090
1091                 if (rule->devname)
1092                         free(rule->devname);
1093                 free(rule);
1094                 rule = tmp;
1095         }
1096 }
1097
1098 void sysfsline(char *line)
1099 {
1100         struct dev_sysfs_rule *sr;
1101         char *w;
1102
1103         sr = xcalloc(1, sizeof(*sr));
1104         for (w = dl_next(line); w != line ; w = dl_next(w)) {
1105                 if (strncasecmp(w, "name=", 5) == 0) {
1106                         char *devname = w + 5;
1107
1108                         if (strncmp(devname, "/dev/md/", 8) == 0) {
1109                                 if (sr->devname)
1110                                         pr_err("Only give one device per SYSFS line: %s\n",
1111                                                 devname);
1112                                 else
1113                                         sr->devname = xstrdup(devname);
1114                         } else {
1115                                 pr_err("%s is an invalid name for an md device - ignored.\n",
1116                                        devname);
1117                         }
1118                 } else if (strncasecmp(w, "uuid=", 5) == 0) {
1119                         char *uuid = w + 5;
1120
1121                         if (sr->uuid_set) {
1122                                 pr_err("Only give one uuid per SYSFS line: %s\n",
1123                                         uuid);
1124                         } else {
1125                                 if (parse_uuid(w + 5, sr->uuid) &&
1126                                     memcmp(sr->uuid, uuid_zero,
1127                                            sizeof(int[4])) != 0)
1128                                         sr->uuid_set = 1;
1129                                 else
1130                                         pr_err("Invalid uuid: %s\n", uuid);
1131                         }
1132                 } else {
1133                         struct sysfs_entry *prop;
1134
1135                         char *sep = strchr(w, '=');
1136
1137                         if (sep == NULL || *(sep + 1) == 0) {
1138                                 pr_err("Cannot parse \"%s\" - ignoring.\n", w);
1139                                 continue;
1140                         }
1141
1142                         prop = xmalloc(sizeof(*prop));
1143                         prop->value = xstrdup(sep + 1);
1144                         *sep = 0;
1145                         prop->name = xstrdup(w);
1146                         prop->next = sr->entry;
1147                         sr->entry = prop;
1148                 }
1149         }
1150
1151         if (!sr->devname && !sr->uuid_set) {
1152                 pr_err("Device name not found in sysfs config entry - ignoring.\n");
1153                 sysfs_rule_free(sr);
1154                 return;
1155         }
1156
1157         sr->next = sysfs_rules;
1158         sysfs_rules = sr;
1159 }