Assemble.c

   1 /*
   2  * mdctl - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001 Neil Brown <neilb@cse.unsw.edu.au>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  *    Author: Neil Brown
  22  *    Email: <neilb@cse.unsw.edu.au>
  23  *    Paper: Neil Brown
  24  *           School of Computer Science and Engineering
  25  *           The University of New South Wales
  26  *           Sydney, 2052
  27  *           Australia
  28  */
  29
  30 #include        "mdctl.h"
  31 #include        "md_p.h"
  32 #include        "md_u.h"
  33
  34 int Assemble(char *mddev, int mdfd,
  35              int uuid[4], int uuidset,
  36              char *conffile, int scan,
  37              int subdevs, char **subdev,
  38              int readonly, int runstop,
  39              int verbose, int force)
  40 {
  41         /*
  42          * The task of Assemble is to submit a
  43          * SET_ARRAY_INFO ioctl with no arg - to prepare
  44          * the array - and then submit a number of
  45          * ADD_NEW_DISK ioctls to add disks into
  46          * the array.  Finally RUN_ARRAY might
  47          * be submitted to start the array.
  48          *
  49          * Much of the work of Assemble is in finding and/or
  50          * checking the disks to make sure they look right.
  51          *
  52          * If mddev is not set, then scan must be and we
  53          *  read through the config file for dev+uuid mapping
  54          *  We recurse, setting mddev, for each device that
  55          *    - isn't running
  56          *    - has a valid uuid (or any uuid if !uuidset
  57          *
  58          * If mddev is set, we try to determine state of md.
  59          *   check version - must be at least 0.90.0
  60          *   check kernel version.  must be at least 2.4.
  61          *    If not, we can possibly fall back on START_ARRAY
  62          *   Try to GET_ARRAY_INFO.
  63          *     If possible, give up
  64          *     If not, try to STOP_ARRAY just to make sure
  65          *
  66          * If !uuidset and scan, look in conf-file for uuid
  67          *       If not found, give up
  68          * If !subdevs and scan and uuidset, get list of devs from conf-file
  69          *
  70          * For each device:
  71          *   Check superblock - discard if bad
  72          *   Check uuid (set if we don't have one) - discard if no match
  73          *   Check superblock similarity if we have a superbloc - discard if different
  74          *   Record events, devicenum, utime
  75          * This should give us a list of devices for the array
  76          * We should collect the most recent event and utime numbers
  77          *
  78          * Count disks with recent enough event count
  79          * While force && !enough disks
  80          *    Choose newest rejected disks, update event count
  81          *     mark clean and rewrite superblock
  82          * If recent kernel:
  83          *    SET_ARRAY_INFO
  84          *    foreach device with recent events : ADD_NEW_DISK
  85          *    if runstop == 1 || "enough" disks and runstop==0 -> RUN_ARRAY
  86          * If old kernel:
  87          *    Check the device numbers in superblock are right
  88          *    update superblock if any changes
  89          *    START_ARRAY
  90          *
  91          */
  92         int old_linux = 0;
  93         int vers;
  94         mdu_array_info_t array;
  95         mddev_dev_t devlist = NULL;
  96         mdp_super_t first_super, super;
  97         struct {
  98                 char *devname;
  99                 int major, minor;
 100                 long long events;
 101                 time_t utime;
 102                 int uptodate;
 103         } devices[MD_SB_DISKS];
 104         int best[MD_SB_DISKS]; /* indexed by raid_disk */
 105         int devcnt = 0, okcnt;
 106         int i;
 107         int most_recent = 0;
 108
 109         if (!mddev && !scan) {
 110                 fputs(Name ": internal error - Assemble called with no devie or scan\n", stderr);
 111                 return 1;
 112         }
 113         if (!mddev) {
 114                 mddev_uuid_t device_list;
 115                 int found = 0;
 116                 device_list = conf_get_uuids(conffile);
 117                 if (!device_list) {
 118                         fprintf(stderr, Name ": No devices found in config file\n");
 119                         return 1;
 120                 }
 121                 while (device_list) {
 122                         if (!uuidset || same_uuid(device_list->uuid,uuid)) {
 123                                 mdfd = open(device_list->devname, O_RDONLY, 0);
 124                                 if (mdfd < 0) {
 125                                         fprintf(stderr,
 126                                                 Name ": error opening %s: %s\n",
 127                                                 device_list->devname,
 128                                                 strerror(errno));
 129                                         continue;
 130                                 }
 131                                 if (Assemble(device_list->devname, mdfd,
 132                                          device_list->uuid, 1,
 133                                          conffile, 1,
 134                                          subdevs, subdev,
 135                                              readonly, runstop, verbose, force)==0)
 136                                         found++;
 137                                 close(mdfd);
 138                         }
 139                         device_list = device_list->next;
 140                 }
 141                 if (found)
 142                         return 0;
 143                 fprintf(stderr,Name ": Did not successful Assemble any devices\n");
 144                 return 1;
 145         }
 146
 147         /*
 148          * Ok, we have an mddev, check it out
 149          */
 150         vers = md_get_version(mdfd);
 151         if (vers <= 0) {
 152                 fprintf(stderr, Name ": %s appears not to be an md device.\n");
 153                 return 1;
 154         }
 155         if (vers < 9000) {
 156                 fprintf(stderr, Name ": Assemble requires driver version 0.90.0 or later.\n"
 157                         "    Upgrade your kernel or try --Build\n");
 158                 return 1;
 159         }
 160         if (get_linux_version() < 2004000)
 161                 old_linux = 1;
 162
 163         if (ioctl(mdfd, GET_ARRAY_INFO, &array)>=0) {
 164                 fprintf(stderr, Name ": device %s already active - cannot assemble it\n",
 165                         mddev);
 166                 return 1;
 167         }
 168         ioctl(mdfd, STOP_ARRAY, NULL); /* just incase it was started but has no content */
 169
 170         /*
 171          * We have a valid mddev, check out uuid
 172          */
 173         if (!uuidset && scan) {
 174                 /* device must be listed with uuid in conf file */
 175                 mddev_uuid_t device_list;
 176                 device_list = conf_get_uuids(conffile);
 177                 while (device_list &&
 178                        strcmp(device_list->devname, mddev) != 0)
 179                         device_list = device_list->next;
 180
 181                 if (!device_list) {
 182                         fprintf(stderr, Name ": --scan set and no uuid found for %s in config file.\n",
 183                                 mddev);
 184                         return 1;
 185                 }
 186                 /* the uuid is safe until next call to conf_get_uuids */
 187                 uuid = device_list->uuid;
 188                 uuidset = 1;
 189         }
 190
 191         /* Now to start looking at devices.
 192          * If no devices were given, but a uuid is available and
 193          * --scan was set, then we should scan all devices listed in the
 194          * config file
 195          *
 196          */
 197         if (subdevs==0 && scan && uuidset)
 198                 devlist = conf_get_devs(conffile);
 199
 200         if (subdevs == 0 && devlist == NULL) {
 201                 fprintf(stderr, Name ": no devices given for %s\n", mddev);
 202                 return 1;
 203         }
 204         /* now for each device */
 205         first_super.md_magic = 0;
 206         for (i=0; i<MD_SB_DISKS; i++)
 207                 best[i] = -1;
 208
 209         while (subdevs || devlist) {
 210                 char *devname;
 211                 int this_uuid[4];
 212                 int dfd;
 213                 struct stat stb;
 214                 int inargv;
 215                 if (subdevs) {
 216                         devname = *subdev++;
 217                         subdevs--;
 218                         inargv=1;
 219                 } else {
 220                         devname = devlist->devname;
 221                         devlist = devlist->next;
 222                         inargv=0;
 223                 }
 224
 225                 dfd = open(devname, O_RDONLY, 0);
 226                 if (dfd < 0) {
 227                         if (inargv || verbose)
 228                                 fprintf(stderr, Name ": cannot open device %s: %s\n",
 229                                         devname, strerror(errno));
 230                         continue;
 231                 }
 232                 if (fstat(dfd, &stb)< 0) {
 233                     /* Impossible! */
 234                     fprintf(stderr, Name ": fstat failed for %s: %s\n",
 235                             devname, strerror(errno));
 236                     close(dfd);
 237                     continue;
 238                 }
 239                 if ((stb.st_mode & S_IFMT) != S_IFBLK) {
 240                     fprintf(stderr, Name ": %d is not a block device.\n",
 241                             devname);
 242                     close(dfd);
 243                     continue;
 244                 }
 245                 if (load_super(dfd, &super)) {
 246                         if (inargv || verbose)
 247                                 fprintf( stderr, Name ": no RAID superblock on %s\n",
 248                                          devname);
 249                         close(dfd);
 250                         continue;
 251                 }
 252                 close(dfd);
 253                 if (compare_super(&first_super, &super)) {
 254                         if (inargv || verbose)
 255                                 fprintf(stderr, Name ": superblock on %s doesn't match\n",
 256                                         devname);
 257                         continue;
 258                 }
 259                 if (uuidset) {
 260                         uuid_from_super(this_uuid, &first_super);
 261                         if (!same_uuid(this_uuid, uuid)) {
 262                                 if (inargv || verbose)
 263                                         fprintf(stderr, Name ": %s has wrong uuid.\n",
 264                                                 devname);
 265                                 continue;
 266                         }
 267                 } else {
 268                         uuid_from_super(uuid, &first_super);
 269                         uuidset = 1;
 270                 }
 271
 272                 /* Ok, this one is at least worth considering */
 273                 if (devcnt >= MD_SB_DISKS) {
 274                     fprintf(stderr, Name ": ouch - too many devices appear to be in this array. Ignoring %s\n",
 275                             devname);
 276                     continue;
 277                 }
 278                 devices[devcnt].devname = devname;
 279                 devices[devcnt].major = MAJOR(stb.st_rdev);
 280                 devices[devcnt].minor = MINOR(stb.st_rdev);
 281                 devices[devcnt].events = md_event(&super);
 282                 devices[devcnt].utime = super.utime;
 283                 devices[devcnt].uptodate = 0;
 284                 if (most_recent < devcnt) {
 285                         if (devices[devcnt].events
 286                             > devices[most_recent].events)
 287                                 most_recent = devcnt;
 288                 }
 289                 i = super.this_disk.raid_disk;
 290                 if (best[i] == -1
 291                     || devices[best[i]].events < devices[devcnt].events) {
 292                         best[i] = devcnt;
 293                 }
 294                 devcnt++;
 295         }
 296
 297         if (devcnt == 0) {
 298                 fprintf(stderr, Name ": no devices found for %s\n",
 299                         mddev);
 300                 return 1;
 301         }
 302         /* now we have some devices that might be suitable.
 303          * I wonder how many
 304          */
 305         okcnt = 0;
 306         for (i=0; i< first_super.raid_disks;i++) {
 307                 int j = best[i];
 308                 if (j < 0) continue;
 309                 if (devices[j].events+1 >=
 310                     devices[most_recent].events) {
 311                         devices[j].uptodate = 1;
 312                         okcnt++;
 313                 }
 314         }
 315         while (force && !enough(first_super.level, first_super.raid_disks, okcnt)) {
 316                 /* Choose the newest best drive which is
 317                  * not up-to-date, update the superblock
 318                  * and add it.
 319                  */
 320                 fprintf(stderr,"NotImplementedYet\n");
 321                 /* FIXME */
 322                 exit(2);
 323         }
 324         /* Almost ready to actually *do* something */
 325         if (!old_linux) {
 326                 if (ioctl(mdfd, SET_ARRAY_INFO, NULL) != 0) {
 327                         fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
 328                                 mddev, strerror(errno));
 329                         return 1;
 330                 }
 331                 /* First, add the raid disks */
 332                 for (i=0; i<first_super.raid_disks; i++) {
 333                         int j = best[i];
 334                         if (devices[j].uptodate) {
 335                                 mdu_disk_info_t disk;
 336                                 memset(&disk, 0, sizeof(disk));
 337                                 disk.major = devices[j].major;
 338                                 disk.minor = devices[j].minor;
 339                                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)!=0) {
 340                                         fprintf(stderr, Name ": failed to add %s to %s: %s\n",
 341                                                 devices[j].devname,
 342                                                 mddev,
 343                                                 strerror(errno));
 344                                 } else
 345                                         okcnt--;
 346                         } else if (verbose)
 347                                 fprintf(stderr, Name ": no uptodate device for slot %d of %s\n",
 348                                         i, mddev);
 349                 }
 350                 if (runstop == 1 ||
 351                     (runstop == 0 &&
 352                      enough(first_super.level, first_super.raid_disks, okcnt))) {
 353                         if (ioctl(mdfd, RUN_ARRAY, NULL)==0)
 354                                 return 0;
 355                         fprintf(stderr, Name ": failed to RUN_ARRAY %s: %s\n",
 356                                 mddev, strerror(errno));
 357                         return 1;
 358                 }
 359                 if (runstop == -1)
 360                         return 0;
 361                 else return 1;
 362         } else {
 363                 /* FIXME */
 364                 return 1;
 365         }
 366 }