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