Create.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2002 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 "mdadm.h"
  31 #include        "md_u.h"
  32 #include        "md_p.h"
  33
  34 int Create(char *mddev, int mdfd,
  35            int chunk, int level, int layout, unsigned long size, int raiddisks, int sparedisks,
  36            int subdevs, mddev_dev_t devlist,
  37            int runstop, int verbose, int force)
  38 {
  39         /*
  40          * Create a new raid array.
  41          *
  42          * First check that necessary details are available
  43          * (i.e. level, raid-disks)
  44          *
  45          * Then check each disk to see what might be on it
  46          * and report anything interesting.
  47          *
  48          * If anything looks odd, and runstop not set,
  49          * abort.
  50          *
  51          * SET_ARRAY_INFO and ADD_NEW_DISK, and
  52          * if runstop==run, or raiddisks diskswere used,
  53          * RUN_ARRAY
  54          */
  55         unsigned long minsize=0, maxsize=0;
  56         char *mindisc = NULL;
  57         char *maxdisc = NULL;
  58         int dnum;
  59         mddev_dev_t dv;
  60         int fail=0, warn=0;
  61         struct stat stb;
  62         int first_missing = MD_SB_DISKS*2;
  63         int missing_disks = 0;
  64         int insert_point = MD_SB_DISKS*2; /* where to insert a missing drive */
  65         mddev_dev_t moved_disk = NULL; /* the disk that was moved out of the insert point */
  66
  67         mdu_array_info_t array;
  68
  69
  70         if (md_get_version(mdfd) < 9000) {
  71                 fprintf(stderr, Name ": Create requires md driver verison 0.90.0 or later\n");
  72                 return 1;
  73         }
  74         if (level == -10) {
  75                 fprintf(stderr,
  76                         Name ": a RAID level is needed to create an array.\n");
  77                 return 1;
  78         }
  79         if (raiddisks < 1) {
  80                 fprintf(stderr,
  81                         Name ": a number of --raid-devices must be given to create an array\n");
  82                 return 1;
  83         }
  84         if (raiddisks < 2 && level >= 4) {
  85                 fprintf(stderr,
  86                         Name ": atleast 2 raid-devices needed for level 4 or 5\n");
  87                 return 1;
  88         }
  89         if (raiddisks+sparedisks > MD_SB_DISKS) {
  90                 fprintf(stderr,
  91                         Name ": too many devices requested: %d+%d > %d\n",
  92                         raiddisks, sparedisks, MD_SB_DISKS);
  93                 return 1;
  94         }
  95         if (subdevs > raiddisks+sparedisks) {
  96                 fprintf(stderr, Name ": You have listed more devices (%d) than are in the array(%d)!\n", subdevs, raiddisks+sparedisks);
  97                 return 1;
  98         }
  99         if (subdevs < raiddisks+sparedisks) {
 100                 fprintf(stderr, Name ": You haven't given enough devices (real or missing) to create this array\n");
 101                 return 1;
 102         }
 103
 104         /* now set some defaults */
 105         if (layout == -1)
 106                 switch(level) {
 107                 default: /* no layout */
 108                         layout = 0;
 109                         break;
 110                 case 5:
 111                         layout = map_name(r5layout, "default");
 112                         if (verbose)
 113                                 fprintf(stderr,
 114                                         Name ": layout defaults to %s\n", map_num(r5layout, layout));
 115                         break;
 116                 }
 117
 118         switch(level) {
 119         case 4:
 120         case 5:
 121         case 0:
 122         case -1: /* linear */
 123                 if (chunk == 0) {
 124                         chunk = 64;
 125                         if (verbose)
 126                                 fprintf(stderr, Name ": chunk size defaults to 64K\n");
 127                 }
 128                 break;
 129         default: /* raid1, multipath */
 130                 if (chunk) {
 131                         chunk = 0;
 132                         if (verbose)
 133                                 fprintf(stderr, Name ": chunk size ignored for this level\n");
 134                 }
 135                 break;
 136         }
 137
 138         /* now look at the subdevs */
 139         array.active_disks = 0;
 140         array.working_disks = 0;
 141         dnum = 0;
 142         for (dv=devlist; dv; dv=dv->next, dnum++) {
 143                 char *dname = dv->devname;
 144                 unsigned long dsize, freesize;
 145                 int fd;
 146                 if (strcasecmp(dname, "missing")==0) {
 147                         if (first_missing > dnum)
 148                                 first_missing = dnum;
 149                         missing_disks ++;
 150                         continue;
 151                 }
 152                 array.working_disks++;
 153                 if (dnum < raiddisks)
 154                         array.active_disks++;
 155                 fd = open(dname, O_RDONLY, 0);
 156                 if (fd <0 ) {
 157                         fprintf(stderr, Name ": Cannot open %s: %s\n",
 158                                 dname, strerror(errno));
 159                         fail=1;
 160                         continue;
 161                 }
 162                 if (ioctl(fd, BLKGETSIZE, &dsize)) {
 163                         fprintf(stderr, Name ": Cannot get size of %s: %s\n",
 164                                 dname, strerror(errno));
 165                         fail = 1;
 166                         close(fd);
 167                         continue;
 168                 }
 169                 if (dsize < MD_RESERVED_SECTORS*2) {
 170                         fprintf(stderr, Name ": %s is too small: %luK\n",
 171                                 dname, dsize/2);
 172                         fail = 1;
 173                         close(fd);
 174                         continue;
 175                 }
 176                 freesize = MD_NEW_SIZE_SECTORS(dsize);
 177                 freesize /= 2;
 178
 179                 if (size && freesize < size) {
 180                         fprintf(stderr, Name ": %s is smaller that given size."
 181                                 " %luK < %luK + superblock\n", dname, freesize, size);
 182                         fail = 1;
 183                         close(fd);
 184                         continue;
 185                 }
 186                 if (maxdisc == NULL || (maxdisc && freesize > maxsize)) {
 187                         maxdisc = dname;
 188                         maxsize = freesize;
 189                 }
 190                 if (mindisc ==NULL || (mindisc && freesize < minsize)) {
 191                         mindisc = dname;
 192                         minsize = freesize;
 193                 }
 194                 warn |= check_ext2(fd, dname);
 195                 warn |= check_reiser(fd, dname);
 196                 warn |= check_raid(fd, dname);
 197                 close(fd);
 198         }
 199         if (fail) {
 200                 fprintf(stderr, Name ": create aborted\n");
 201                 return 1;
 202         }
 203         if (size == 0) {
 204                 if (mindisc == NULL) {
 205                         fprintf(stderr, Name ": no size and no drives given - aborting create.\n");
 206                         return 1;
 207                 }
 208                 size = minsize;
 209                 if (verbose && level>0)
 210                         fprintf(stderr, Name ": size set to %luK\n", size);
 211         }
 212         if (level >= 1 && ((maxsize-size)*100 > maxsize)) {
 213                 fprintf(stderr, Name ": largest drive (%s) exceed size (%luK) by more than 1%%\n",
 214                         maxdisc, size);
 215                 warn = 1;
 216         }
 217
 218         if (warn) {
 219                 if (runstop!= 1) {
 220                         if (!ask("Continue creating array? ")) {
 221                                 fprintf(stderr, Name ": create aborted.\n");
 222                                 return 1;
 223                         }
 224                 } else {
 225                         if (verbose)
 226                                 fprintf(stderr, Name ": creation continuing despite oddities due to --run\n");
 227                 }
 228         }
 229
 230         /* If this is  raid5, we want to configure the last active slot
 231          * as missing, so that a reconstruct happens (faster than re-parity)
 232          */
 233         if (force == 0 && level == 5 && first_missing >= raiddisks) {
 234                 insert_point = raiddisks-1;
 235                 sparedisks++;
 236                 array.active_disks--;
 237                 missing_disks++;
 238         }
 239
 240         /* Ok, lets try some ioctls */
 241
 242         array.level = level;
 243         array.size = size;
 244         array.raid_disks = raiddisks;
 245         /* The kernel should *know* what md_minor we are dealing
 246          * with, but it chooses to trust me instead. Sigh
 247          */
 248         array.md_minor = 0;
 249         if (fstat(mdfd, &stb)==0)
 250                 array.md_minor = MINOR(stb.st_rdev);
 251         array.not_persistent = 0;
 252         if (level == 5 && (insert_point < raiddisks || first_missing < raiddisks))
 253                 array.state = 1; /* clean, but one drive will be missing */
 254         else
 255                 array.state = 0; /* not clean, but no errors */
 256
 257         /* There is lots of redundancy in these disk counts,
 258          * raid_disks is the most meaningful value
 259          *          it describes the geometry of the array
 260          *          it is constant
 261          * nr_disks is total number of used slots.
 262          *          it should be raid_disks+spare_disks
 263          * spare_disks is the number of extra disks present
 264          *          see above
 265          * active_disks is the number of working disks in
 266          *          active slots. (With raid_disks)
 267          * working_disks is the total number of working disks,
 268          *          including spares
 269          * failed_disks is the number of disks marked failed
 270          *
 271          * Ideally, the kernel would keep these (except raid_disks)
 272          * up-to-date as we ADD_NEW_DISK, but it doesn't (yet).
 273          * So for now, we assume that all raid and spare
 274          * devices will be given.
 275          */
 276         array.spare_disks=sparedisks;
 277         array.failed_disks=missing_disks;
 278         array.nr_disks = array.working_disks + array.failed_disks;
 279         array.layout = layout;
 280         array.chunk_size = chunk*1024;
 281
 282         if (ioctl(mdfd, SET_ARRAY_INFO, &array)) {
 283                 fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
 284                         mddev, strerror(errno));
 285                 return 1;
 286         }
 287
 288         for (dnum=0, dv = devlist ; dv ; dv=(dv->next)?(dv->next):moved_disk, dnum++) {
 289                 int fd;
 290                 struct stat stb;
 291                 mdu_disk_info_t disk;
 292
 293                 disk.number = dnum;
 294                 if (dnum == insert_point) {
 295                         moved_disk = dv;
 296                 }
 297                 disk.raid_disk = disk.number;
 298                 if (disk.raid_disk < raiddisks)
 299                         disk.state = 6; /* active and in sync */
 300                 else
 301                         disk.state = 0;
 302                 if (dnum == insert_point ||
 303                     strcasecmp(dv->devname, "missing")==0) {
 304                         disk.major = 0;
 305                         disk.minor = 0;
 306                         disk.state = 1; /* faulty */
 307                 } else {
 308                         fd = open(dv->devname, O_RDONLY, 0);
 309                         if (fd < 0) {
 310                                 fprintf(stderr, Name ": failed to open %s after earlier success - aborting\n",
 311                                         dv->devname);
 312                                 return 1;
 313                         }
 314                         fstat(fd, &stb);
 315                         disk.major = MAJOR(stb.st_rdev);
 316                         disk.minor = MINOR(stb.st_rdev);
 317                         close(fd);
 318                 }
 319                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)) {
 320                         fprintf(stderr, Name ": ADD_NEW_DISK for %s failed: %s\n",
 321                                 dv->devname, strerror(errno));
 322                         return 1;
 323                 }
 324                 if (dv == moved_disk && dnum != insert_point) break;
 325         }
 326
 327         /* param is not actually used */
 328         if (runstop == 1 || subdevs >= raiddisks) {
 329                 mdu_param_t param;
 330                 if (ioctl(mdfd, RUN_ARRAY, &param)) {
 331                         fprintf(stderr, Name ": RUN_ARRAY failed: %s\n",
 332                                 strerror(errno));
 333                         return 1;
 334                 }
 335                 fprintf(stderr, Name ": array %s started.\n", mddev);
 336         } else {
 337                 fprintf(stderr, Name ": not starting array - not enough devices.\n");
 338         }
 339         return 0;
 340 }