Add 'supertype' arg to almost all metadata methods.
[thirdparty/mdadm.git] / Assemble.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        <ctype.h>
32
33 static int name_matches(char *found, char *required, char *homehost)
34 {
35         /* See if the name found matches the required name, possibly
36          * prefixed with 'homehost'
37          */
38         char fnd[33];
39
40         strncpy(fnd, found, 32);
41         fnd[32] = 0;
42         if (strcmp(found, required)==0)
43                 return 1;
44         if (homehost) {
45                 int l = strlen(homehost);
46                 if (l < 32 && fnd[l] == ':' &&
47                     strcmp(fnd+l+1, required)==0)
48                         return 1;
49         }
50         return 0;
51 }
52
53 int Assemble(struct supertype *st, char *mddev, int mdfd,
54              mddev_ident_t ident,
55              mddev_dev_t devlist, char *backup_file,
56              int readonly, int runstop,
57              char *update, char *homehost,
58              int verbose, int force)
59 {
60         /*
61          * The task of Assemble is to find a collection of
62          * devices that should (according to their superblocks)
63          * form an array, and to give this collection to the MD driver.
64          * In Linux-2.4 and later, this involves submitting a
65          * SET_ARRAY_INFO ioctl with no arg - to prepare
66          * the array - and then submit a number of
67          * ADD_NEW_DISK ioctls to add disks into
68          * the array.  Finally RUN_ARRAY might
69          * be submitted to start the array.
70          *
71          * Much of the work of Assemble is in finding and/or
72          * checking the disks to make sure they look right.
73          *
74          * If mddev is not set, then scan must be set and we
75          *  read through the config file for dev+uuid mapping
76          *  We recurse, setting mddev, for each device that
77          *    - isn't running
78          *    - has a valid uuid (or any uuid if !uuidset)
79          *
80          * If mddev is set, we try to determine state of md.
81          *   check version - must be at least 0.90.0
82          *   check kernel version.  must be at least 2.4.
83          *    If not, we can possibly fall back on START_ARRAY
84          *   Try to GET_ARRAY_INFO.
85          *     If possible, give up
86          *     If not, try to STOP_ARRAY just to make sure
87          *
88          * If !uuidset and scan, look in conf-file for uuid
89          *       If not found, give up
90          * If !devlist and scan and uuidset, get list of devs from conf-file
91          *
92          * For each device:
93          *   Check superblock - discard if bad
94          *   Check uuid (set if we don't have one) - discard if no match
95          *   Check superblock similarity if we have a superblock - discard if different
96          *   Record events, devicenum
97          * This should give us a list of devices for the array
98          * We should collect the most recent event number
99          *
100          * Count disks with recent enough event count
101          * While force && !enough disks
102          *    Choose newest rejected disks, update event count
103          *     mark clean and rewrite superblock
104          * If recent kernel:
105          *    SET_ARRAY_INFO
106          *    foreach device with recent events : ADD_NEW_DISK
107          *    if runstop == 1 || "enough" disks and runstop==0 -> RUN_ARRAY
108          * If old kernel:
109          *    Check the device numbers in superblock are right
110          *    update superblock if any changes
111          *    START_ARRAY
112          *
113          */
114         int clean = 0;
115         int must_close = 0;
116         int old_linux = 0;
117         int vers = 0; /* Keep gcc quite - it really is initialised */
118         void *first_super = NULL, *super = NULL;
119         struct {
120                 char *devname;
121                 unsigned int major, minor;
122                 unsigned int oldmajor, oldminor;
123                 long long events;
124                 int uptodate;
125                 int state;
126                 int raid_disk;
127                 int disk_nr;
128         } *devices;
129         int *best = NULL; /* indexed by raid_disk */
130         unsigned int bestcnt = 0;
131         int devcnt = 0;
132         unsigned int okcnt, sparecnt;
133         unsigned int req_cnt;
134         unsigned int i;
135         int most_recent = 0;
136         int chosen_drive;
137         int change = 0;
138         int inargv = 0;
139         int bitmap_done;
140         int start_partial_ok = (runstop >= 0) && (force || devlist==NULL || mdfd < 0);
141         unsigned int num_devs;
142         mddev_dev_t tmpdev;
143         struct mdinfo info;
144         char *avail;
145         int nextspare = 0;
146
147         if (get_linux_version() < 2004000)
148                 old_linux = 1;
149
150         if (mdfd >= 0) {
151                 vers = md_get_version(mdfd);
152                 if (vers <= 0) {
153                         fprintf(stderr, Name ": %s appears not to be an md device.\n", mddev);
154                         return 1;
155                 }
156                 if (vers < 9000) {
157                         fprintf(stderr, Name ": Assemble requires driver version 0.90.0 or later.\n"
158                                 "    Upgrade your kernel or try --build\n");
159                         return 1;
160                 }
161
162                 if (ioctl(mdfd, GET_ARRAY_INFO, &info.array)>=0) {
163                         fprintf(stderr, Name ": device %s already active - cannot assemble it\n",
164                                 mddev);
165                         return 1;
166                 }
167                 ioctl(mdfd, STOP_ARRAY, NULL); /* just incase it was started but has no content */
168         }
169         /*
170          * If any subdevs are listed, then any that don't
171          * match ident are discarded.  Remainder must all match and
172          * become the array.
173          * If no subdevs, then we scan all devices in the config file, but
174          * there must be something in the identity
175          */
176
177         if (!devlist &&
178             ident->uuid_set == 0 &&
179             ident->super_minor < 0 &&
180             ident->devices == NULL) {
181                 fprintf(stderr, Name ": No identity information available for %s - cannot assemble.\n",
182                         mddev ? mddev : "further assembly");
183                 return 1;
184         }
185         if (devlist == NULL)
186                 devlist = conf_get_devs();
187         else if (mdfd >= 0)
188                 inargv = 1;
189
190  try_again:
191
192         tmpdev = devlist; num_devs = 0;
193         while (tmpdev) {
194                 if (tmpdev->used)
195                         tmpdev->used = 2;
196                 else
197                         num_devs++;
198                 tmpdev = tmpdev->next;
199         }
200         devices = malloc(num_devs * sizeof(*devices));
201
202         if (!st && ident->st) st = ident->st;
203
204         if (verbose>0)
205             fprintf(stderr, Name ": looking for devices for %s\n",
206                     mddev ? mddev : "further assembly");
207
208         /* first walk the list of devices to find a consistent set
209          * that match the criterea, if that is possible.
210          * We flag the one we like with 'used'.
211          */
212         for (tmpdev = devlist;
213              tmpdev;
214              tmpdev = tmpdev->next) {
215                 char *devname = tmpdev->devname;
216                 int dfd;
217                 struct stat stb;
218                 struct supertype *tst = st;
219
220                 if (tmpdev->used > 1) continue;
221
222                 if (ident->devices &&
223                     !match_oneof(ident->devices, devname)) {
224                         if ((inargv && verbose>=0) || verbose > 0)
225                                 fprintf(stderr, Name ": %s is not one of %s\n", devname, ident->devices);
226                         continue;
227                 }
228
229                 dfd = dev_open(devname, O_RDONLY|O_EXCL);
230                 if (dfd < 0) {
231                         if ((inargv && verbose >= 0) || verbose > 0)
232                                 fprintf(stderr, Name ": cannot open device %s: %s\n",
233                                         devname, strerror(errno));
234                         tmpdev->used = 2;
235                 } else if (fstat(dfd, &stb)< 0) {
236                         /* Impossible! */
237                         fprintf(stderr, Name ": fstat failed for %s: %s\n",
238                                 devname, strerror(errno));
239                         tmpdev->used = 2;
240                 } else if ((stb.st_mode & S_IFMT) != S_IFBLK) {
241                         fprintf(stderr, Name ": %s is not a block device.\n",
242                                 devname);
243                         tmpdev->used = 2;
244                 } else if (!tst && (tst = guess_super(dfd)) == NULL) {
245                         if ((inargv && verbose >= 0) || verbose > 0)
246                                 fprintf(stderr, Name ": no recogniseable superblock on %s\n",
247                                         devname);
248                         tmpdev->used = 2;
249                 } else if (tst->ss->load_super(tst,dfd, &super, NULL)) {
250                         if ((inargv && verbose >= 0) || verbose > 0)
251                                 fprintf( stderr, Name ": no RAID superblock on %s\n",
252                                          devname);
253                 } else {
254                         tst->ss->getinfo_super(tst, &info, super);
255                 }
256                 if (dfd >= 0) close(dfd);
257
258                 if (ident->uuid_set && (!update || strcmp(update, "uuid")!= 0) &&
259                     (!super || same_uuid(info.uuid, ident->uuid, tst->ss->swapuuid)==0)) {
260                         if ((inargv && verbose >= 0) || verbose > 0)
261                                 fprintf(stderr, Name ": %s has wrong uuid.\n",
262                                         devname);
263                         goto loop;
264                 }
265                 if (ident->name[0] && (!update || strcmp(update, "name")!= 0) &&
266                     (!super || name_matches(info.name, ident->name, homehost)==0)) {
267                         if ((inargv && verbose >= 0) || verbose > 0)
268                                 fprintf(stderr, Name ": %s has wrong name.\n",
269                                         devname);
270                         goto loop;
271                 }
272                 if (ident->super_minor != UnSet &&
273                     (!super || ident->super_minor != info.array.md_minor)) {
274                         if ((inargv && verbose >= 0) || verbose > 0)
275                                 fprintf(stderr, Name ": %s has wrong super-minor.\n",
276                                         devname);
277                         goto loop;
278                 }
279                 if (ident->level != UnSet &&
280                     (!super|| ident->level != info.array.level)) {
281                         if ((inargv && verbose >= 0) || verbose > 0)
282                                 fprintf(stderr, Name ": %s has wrong raid level.\n",
283                                         devname);
284                         goto loop;
285                 }
286                 if (ident->raid_disks != UnSet &&
287                     (!super || ident->raid_disks!= info.array.raid_disks)) {
288                         if ((inargv && verbose >= 0) || verbose > 0)
289                                 fprintf(stderr, Name ": %s requires wrong number of drives.\n",
290                                         devname);
291                         goto loop;
292                 }
293                 if (mdfd < 0) {
294                         if (tst == NULL || super == NULL)
295                                 continue;
296                         if (update == NULL &&
297                             tst->ss->match_home(tst, super, homehost)==0) {
298                                 if ((inargv && verbose >= 0) || verbose > 0)
299                                         fprintf(stderr, Name ": %s is not built for host %s.\n",
300                                                 devname, homehost);
301                                 /* Auto-assemble, and this is not a usable host */
302                                 /* if update != NULL, we are updating the host
303                                  * name... */
304                                 goto loop;
305                         }
306                 }
307                 /* If we are this far, then we are nearly commited to this device.
308                  * If the super_block doesn't exist, or doesn't match others,
309                  * then we probably cannot continue
310                  * However if one of the arrays is for the homehost, and
311                  * the other isn't that can disambiguate.
312                  */
313
314                 if (!super) {
315                         fprintf(stderr, Name ": %s has no superblock - assembly aborted\n",
316                                 devname);
317                         st->ss->free_super(st, first_super);
318                         return 1;
319                 }
320
321                 if (st == NULL)
322                         st = tst;
323                 if (st->ss != tst->ss ||
324                     st->minor_version != tst->minor_version ||
325                     st->ss->compare_super(&first_super, super) != 0) {
326                         /* Some mismatch. If exactly one array matches this host,
327                          * we can resolve on that one.
328                          * Or, if we are auto assembling, we just ignore the second
329                          * for now.
330                          */
331                         if (mdfd < 0)
332                                 goto loop;
333                         if (homehost) {
334                                 int first = st->ss->match_home(st, first_super,
335                                                                homehost);
336                                 int last = tst->ss->match_home(tst, super,
337                                                                homehost);
338                                 if (first+last == 1) {
339                                         /* We can do something */
340                                         if (first) {/* just ignore this one */
341                                                 if ((inargv && verbose >= 0) || verbose > 0)
342                                                         fprintf(stderr, Name ": %s misses out due to wrong homehost\n",
343                                                                 devname);
344                                                 goto loop;
345                                         } else { /* reject all those sofar */
346                                                 mddev_dev_t td;
347                                                 if ((inargv && verbose >= 0) || verbose > 0)
348                                                         fprintf(stderr, Name ": %s overrides previous devices due to good homehost\n",
349                                                                 devname);
350                                                 for (td=devlist; td != tmpdev; td=td->next)
351                                                         if (td->used == 1)
352                                                                 td->used = 0;
353                                                 tmpdev->used = 1;
354                                                 goto loop;
355                                         }
356                                 }
357                         }
358                         fprintf(stderr, Name ": superblock on %s doesn't match others - assembly aborted\n",
359                                 devname);
360                         tst->ss->free_super(tst, super);
361                         st->ss->free_super(st, first_super);
362                         return 1;
363                 }
364
365                 tmpdev->used = 1;
366
367         loop:
368                 if (super)
369                         tst->ss->free_super(tst, super);
370                 super = NULL;
371         }
372
373         if (mdfd < 0) {
374                 /* So... it is up to me to open the device.
375                  * We create a name '/dev/md/XXX' based on the info in the
376                  * superblock, and call open_mddev on that
377                  */
378                 mdu_array_info_t inf;
379                 char *c;
380                 if (!first_super) {
381                         return 2;
382                 }
383                 st->ss->getinfo_super(st, &info, first_super);
384                 c = strchr(info.name, ':');
385                 if (c) c++; else c= info.name;
386                 if (isdigit(*c) && ((ident->autof & 7)==4 || (ident->autof&7)==6))
387                         /* /dev/md/d0 style for partitionable */
388                         asprintf(&mddev, "/dev/md/d%s", c);
389                 else
390                         asprintf(&mddev, "/dev/md/%s", c);
391                 mdfd = open_mddev(mddev, ident->autof);
392                 if (mdfd < 0) {
393                         st->ss->free_super(st, first_super);
394                         free(devices);
395                         first_super = NULL;
396                         goto try_again;
397                 }
398                 vers = md_get_version(mdfd);
399                 if (ioctl(mdfd, GET_ARRAY_INFO, &inf)==0) {
400                         for (tmpdev = devlist ;
401                              tmpdev && tmpdev->used != 1;
402                              tmpdev = tmpdev->next)
403                                 ;
404                         fprintf(stderr, Name ": %s already active, cannot restart it!\n", mddev);
405                         if (tmpdev)
406                                 fprintf(stderr, Name ":   %s needed for %s...\n",
407                                         mddev, tmpdev->devname);
408                         close(mdfd);
409                         mdfd = -1;
410                         st->ss->free_super(st, first_super);
411                         free(devices);
412                         first_super = NULL;
413                         goto try_again;
414                 }
415                 must_close = 1;
416         }
417
418         /* Ok, no bad inconsistancy, we can try updating etc */
419         bitmap_done = 0;
420         for (tmpdev = devlist; tmpdev; tmpdev=tmpdev->next) if (tmpdev->used == 1) {
421                 char *devname = tmpdev->devname;
422                 struct stat stb;
423                 /* looks like a good enough match to update the super block if needed */
424 #ifndef MDASSEMBLE
425                 if (update) {
426                         int dfd;
427                         /* prepare useful information in info structures */
428                         struct stat stb2;
429                         fstat(mdfd, &stb2);
430
431                         if (strcmp(update, "uuid")==0 &&
432                             !ident->uuid_set) {
433                                 int rfd;
434                                 if ((rfd = open("/dev/urandom", O_RDONLY)) < 0 ||
435                                     read(rfd, ident->uuid, 16) != 16) {
436                                         *(__u32*)(ident->uuid) = random();
437                                         *(__u32*)(ident->uuid+1) = random();
438                                         *(__u32*)(ident->uuid+2) = random();
439                                         *(__u32*)(ident->uuid+3) = random();
440                                 }
441                                 if (rfd >= 0) close(rfd);
442                         }
443                         dfd = dev_open(devname, O_RDWR|O_EXCL);
444
445                         remove_partitions(dfd);
446
447                         st->ss->load_super(st, dfd, &super, NULL);
448                         st->ss->getinfo_super(st, &info, super);
449
450                         memcpy(info.uuid, ident->uuid, 16);
451                         strcpy(info.name, ident->name);
452                         info.array.md_minor = minor(stb2.st_rdev);
453
454                         st->ss->update_super(st, &info, super, update,
455                                              devname, verbose,
456                                              ident->uuid_set, homehost);
457                         if (strcmp(update, "uuid")==0 &&
458                             !ident->uuid_set) {
459                                 ident->uuid_set = 1;
460                                 memcpy(ident->uuid, info.uuid, 16);
461                         }
462                         if (dfd < 0)
463                                 fprintf(stderr, Name ": Cannot open %s for superblock update\n",
464                                         devname);
465                         else if (st->ss->store_super(st, dfd, super))
466                                 fprintf(stderr, Name ": Could not re-write superblock on %s.\n",
467                                         devname);
468                         if (dfd >= 0)
469                                 close(dfd);
470
471                         if (strcmp(update, "uuid")==0 &&
472                             ident->bitmap_fd >= 0 && !bitmap_done) {
473                                 if (bitmap_update_uuid(ident->bitmap_fd, info.uuid, st->ss->swapuuid) != 0)
474                                         fprintf(stderr, Name ": Could not update uuid on external bitmap.\n");
475                                 else
476                                         bitmap_done = 1;
477                         }
478                 } else
479 #endif
480                 {
481                         int dfd;
482                         dfd = dev_open(devname, O_RDWR|O_EXCL);
483
484                         remove_partitions(dfd);
485
486                         st->ss->load_super(st, dfd, &super, NULL);
487                         st->ss->getinfo_super(st, &info, super);
488                         close(dfd);
489                 }
490
491                 stat(devname, &stb);
492
493                 if (verbose > 0)
494                         fprintf(stderr, Name ": %s is identified as a member of %s, slot %d.\n",
495                                 devname, mddev, info.disk.raid_disk);
496                 devices[devcnt].devname = devname;
497                 devices[devcnt].major = major(stb.st_rdev);
498                 devices[devcnt].minor = minor(stb.st_rdev);
499                 devices[devcnt].oldmajor = info.disk.major;
500                 devices[devcnt].oldminor = info.disk.minor;
501                 devices[devcnt].events = info.events;
502                 devices[devcnt].raid_disk = info.disk.raid_disk;
503                 devices[devcnt].disk_nr = info.disk.number;
504                 devices[devcnt].uptodate = 0;
505                 devices[devcnt].state = info.disk.state;
506                 if (most_recent < devcnt) {
507                         if (devices[devcnt].events
508                             > devices[most_recent].events)
509                                 most_recent = devcnt;
510                 }
511                 if (info.array.level == -4)
512                         /* with multipath, the raid_disk from the superblock is meaningless */
513                         i = devcnt;
514                 else
515                         i = devices[devcnt].raid_disk;
516                 if (i+1 == 0) {
517                         if (nextspare < info.array.raid_disks)
518                                 nextspare = info.array.raid_disks;
519                         i = nextspare++;
520                 } else {
521                         if (i >= info.array.raid_disks &&
522                             i >= nextspare)
523                                 nextspare = i+1;
524                 }
525                 if (i < 10000) {
526                         if (i >= bestcnt) {
527                                 unsigned int newbestcnt = i+10;
528                                 int *newbest = malloc(sizeof(int)*newbestcnt);
529                                 unsigned int c;
530                                 for (c=0; c < newbestcnt; c++)
531                                         if (c < bestcnt)
532                                                 newbest[c] = best[c];
533                                         else
534                                                 newbest[c] = -1;
535                                 if (best)free(best);
536                                 best = newbest;
537                                 bestcnt = newbestcnt;
538                         }
539                         if (best[i] >=0 &&
540                             devices[best[i]].events == devices[devcnt].events &&
541                             devices[best[i]].minor != devices[devcnt].minor &&
542                             st->ss->major == 0 &&
543                             info.array.level != -4) {
544                                 /* two different devices with identical superblock.
545                                  * Could be a mis-detection caused by overlapping
546                                  * partitions.  fail-safe.
547                                  */
548                                 fprintf(stderr, Name ": WARNING %s and %s appear"
549                                         " to have very similar superblocks.\n"
550                                         "      If they are really different, "
551                                         "please --zero the superblock on one\n"
552                                         "      If they are the same or overlap,"
553                                         " please remove one from %s.\n",
554                                         devices[best[i]].devname, devname,
555                                         inargv ? "the list" :
556                                            "the\n      DEVICE list in mdadm.conf"
557                                         );
558                                 if (must_close) close(mdfd);
559                                 return 1;
560                         }
561                         if (best[i] == -1
562                             || devices[best[i]].events < devices[devcnt].events)
563                                 best[i] = devcnt;
564                 }
565                 devcnt++;
566
567                 if (super)
568                         st->ss->free_super(st, super);
569                 super = NULL;
570         }
571
572         if (update && strcmp(update, "byteorder")==0)
573                 st->minor_version = 90;
574
575         if (devcnt == 0) {
576                 fprintf(stderr, Name ": no devices found for %s\n",
577                         mddev);
578                 st->ss->free_super(st, first_super);
579                 if (must_close) close(mdfd);
580                 return 1;
581         }
582
583         st->ss->getinfo_super(st, &info, first_super);
584         clean = info.array.state & 1;
585
586         /* now we have some devices that might be suitable.
587          * I wonder how many
588          */
589         avail = malloc(info.array.raid_disks);
590         memset(avail, 0, info.array.raid_disks);
591         okcnt = 0;
592         sparecnt=0;
593         for (i=0; i< bestcnt ;i++) {
594                 int j = best[i];
595                 int event_margin = 1; /* always allow a difference of '1'
596                                        * like the kernel does
597                                        */
598                 if (j < 0) continue;
599                 /* note: we ignore error flags in multipath arrays
600                  * as they don't make sense
601                  */
602                 if (info.array.level != -4)
603                         if (!(devices[j].state & (1<<MD_DISK_SYNC))) {
604                                 if (!(devices[j].state & (1<<MD_DISK_FAULTY)))
605                                         sparecnt++;
606                                 continue;
607                         }
608                 if (devices[j].events+event_margin >=
609                     devices[most_recent].events) {
610                         devices[j].uptodate = 1;
611                         if (i < info.array.raid_disks) {
612                                 okcnt++;
613                                 avail[i]=1;
614                         } else
615                                 sparecnt++;
616                 }
617         }
618         while (force && !enough(info.array.level, info.array.raid_disks,
619                                 info.array.layout, 1,
620                                 avail, okcnt)) {
621                 /* Choose the newest best drive which is
622                  * not up-to-date, update the superblock
623                  * and add it.
624                  */
625                 int fd;
626                 long long current_events;
627                 chosen_drive = -1;
628                 for (i=0; i<info.array.raid_disks && i < bestcnt; i++) {
629                         int j = best[i];
630                         if (j>=0 &&
631                             !devices[j].uptodate &&
632                             devices[j].events > 0 &&
633                             (chosen_drive < 0 ||
634                              devices[j].events > devices[chosen_drive].events))
635                                 chosen_drive = j;
636                 }
637                 if (chosen_drive < 0)
638                         break;
639                 current_events = devices[chosen_drive].events;
640         add_another:
641                 if (verbose >= 0)
642                         fprintf(stderr, Name ": forcing event count in %s(%d) from %d upto %d\n",
643                                 devices[chosen_drive].devname, devices[chosen_drive].raid_disk,
644                                 (int)(devices[chosen_drive].events),
645                                 (int)(devices[most_recent].events));
646                 fd = dev_open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
647                 if (fd < 0) {
648                         fprintf(stderr, Name ": Couldn't open %s for write - not updating\n",
649                                 devices[chosen_drive].devname);
650                         devices[chosen_drive].events = 0;
651                         continue;
652                 }
653                 if (st->ss->load_super(st,fd, &super, NULL)) {
654                         close(fd);
655                         fprintf(stderr, Name ": RAID superblock disappeared from %s - not updating.\n",
656                                 devices[chosen_drive].devname);
657                         devices[chosen_drive].events = 0;
658                         continue;
659                 }
660                 info.events = devices[most_recent].events;
661                 st->ss->update_super(st, &info, super, "force-one",
662                                      devices[chosen_drive].devname, verbose,
663                                      0, NULL);
664
665                 if (st->ss->store_super(st, fd, super)) {
666                         close(fd);
667                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
668                                 devices[chosen_drive].devname);
669                         devices[chosen_drive].events = 0;
670                         st->ss->free_super(st, super);
671                         continue;
672                 }
673                 close(fd);
674                 devices[chosen_drive].events = devices[most_recent].events;
675                 devices[chosen_drive].uptodate = 1;
676                 avail[chosen_drive] = 1;
677                 okcnt++;
678                 st->ss->free_super(st, super);
679
680                 /* If there are any other drives of the same vintage,
681                  * add them in as well.  We can't lose and we might gain
682                  */
683                 for (i=0; i<info.array.raid_disks && i < bestcnt ; i++) {
684                         int j = best[i];
685                         if (j >= 0 &&
686                             !devices[j].uptodate &&
687                             devices[j].events > 0 &&
688                             devices[j].events == current_events) {
689                                 chosen_drive = j;
690                                 goto add_another;
691                         }
692                 }
693         }
694
695         /* Now we want to look at the superblock which the kernel will base things on
696          * and compare the devices that we think are working with the devices that the
697          * superblock thinks are working.
698          * If there are differences and --force is given, then update this chosen
699          * superblock.
700          */
701         chosen_drive = -1;
702         super = NULL;
703         for (i=0; chosen_drive < 0 && i<bestcnt; i++) {
704                 int j = best[i];
705                 int fd;
706
707                 if (j<0)
708                         continue;
709                 if (!devices[j].uptodate)
710                         continue;
711                 chosen_drive = j;
712                 if ((fd=dev_open(devices[j].devname, O_RDONLY|O_EXCL))< 0) {
713                         fprintf(stderr, Name ": Cannot open %s: %s\n",
714                                 devices[j].devname, strerror(errno));
715                         if (must_close) close(mdfd);
716                         return 1;
717                 }
718                 if (st->ss->load_super(st,fd, &super, NULL)) {
719                         close(fd);
720                         fprintf(stderr, Name ": RAID superblock has disappeared from %s\n",
721                                 devices[j].devname);
722                         if (must_close) close(mdfd);
723                         return 1;
724                 }
725                 close(fd);
726         }
727         if (super == NULL) {
728                 fprintf(stderr, Name ": No suitable drives found for %s\n", mddev);
729                 if (must_close) close(mdfd);
730                 return 1;
731         }
732         st->ss->getinfo_super(st, &info, super);
733         for (i=0; i<bestcnt; i++) {
734                 int j = best[i];
735                 unsigned int desired_state;
736
737                 if (i < info.array.raid_disks)
738                         desired_state = (1<<MD_DISK_ACTIVE) | (1<<MD_DISK_SYNC);
739                 else
740                         desired_state = 0;
741
742                 if (j<0)
743                         continue;
744                 if (!devices[j].uptodate)
745                         continue;
746                 info.disk.number = devices[j].disk_nr;
747                 info.disk.raid_disk = i;
748                 info.disk.state = desired_state;
749
750                 if (devices[j].uptodate &&
751                     st->ss->update_super(st, &info, super, "assemble", NULL,
752                                          verbose, 0, NULL)) {
753                         if (force) {
754                                 if (verbose >= 0)
755                                         fprintf(stderr, Name ": "
756                                                 "clearing FAULTY flag for device %d in %s for %s\n",
757                                                 j, mddev, devices[j].devname);
758                                 change = 1;
759                         } else {
760                                 if (verbose >= -1)
761                                         fprintf(stderr, Name ": "
762                                                 "device %d in %s has wrong state in superblock, but %s seems ok\n",
763                                                 i, mddev, devices[j].devname);
764                         }
765                 }
766 #if 0
767                 if (!devices[j].uptodate &&
768                     !(super.disks[i].state & (1 << MD_DISK_FAULTY))) {
769                         fprintf(stderr, Name ": devices %d of %s is not marked FAULTY in superblock, but cannot be found\n",
770                                 i, mddev);
771                 }
772 #endif
773         }
774         if (force && !clean &&
775             !enough(info.array.level, info.array.raid_disks,
776                     info.array.layout, clean,
777                     avail, okcnt)) {
778                 change += st->ss->update_super(st, &info, super, "force-array",
779                                         devices[chosen_drive].devname, verbose,
780                                                0, NULL);
781                 clean = 1;
782         }
783
784         if (change) {
785                 int fd;
786                 fd = dev_open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
787                 if (fd < 0) {
788                         fprintf(stderr, Name ": Could not open %s for write - cannot Assemble array.\n",
789                                 devices[chosen_drive].devname);
790                         if (must_close) close(mdfd);
791                         return 1;
792                 }
793                 if (st->ss->store_super(st, fd, super)) {
794                         close(fd);
795                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
796                                 devices[chosen_drive].devname);
797                         if (must_close) close(mdfd);
798                         return 1;
799                 }
800                 close(fd);
801         }
802
803         /* If we are in the middle of a reshape we may need to restore saved data
804          * that was moved aside due to the reshape overwriting live data
805          * The code of doing this lives in Grow.c
806          */
807 #ifndef MDASSEMBLE
808         if (info.reshape_active) {
809                 int err = 0;
810                 int *fdlist = malloc(sizeof(int)* bestcnt);
811                 for (i=0; i<bestcnt; i++) {
812                         int j = best[i];
813                         if (j >= 0) {
814                                 fdlist[i] = dev_open(devices[j].devname, O_RDWR|O_EXCL);
815                                 if (fdlist[i] < 0) {
816                                         fprintf(stderr, Name ": Could not open %s for write - cannot Assemble array.\n",
817                                                 devices[j].devname);
818                                         err = 1;
819                                         break;
820                                 }
821                         } else
822                                 fdlist[i] = -1;
823                 }
824                 if (!err)
825                         err = Grow_restart(st, &info, fdlist, bestcnt, backup_file);
826                 while (i>0) {
827                         i--;
828                         if (fdlist[i]>=0) close(fdlist[i]);
829                 }
830                 if (err) {
831                         fprintf(stderr, Name ": Failed to restore critical section for reshape, sorry.\n");
832                         if (must_close) close(mdfd);
833                         return err;
834                 }
835         }
836 #endif
837         /* count number of in-sync devices according to the superblock.
838          * We must have this number to start the array without -s or -R
839          */
840         req_cnt = info.array.working_disks;
841
842         /* Almost ready to actually *do* something */
843         if (!old_linux) {
844                 int rv;
845                 if ((vers % 100) >= 1) { /* can use different versions */
846                         mdu_array_info_t inf;
847                         memset(&inf, 0, sizeof(inf));
848                         inf.major_version = st->ss->major;
849                         inf.minor_version = st->minor_version;
850                         rv = ioctl(mdfd, SET_ARRAY_INFO, &inf);
851                 } else
852                         rv = ioctl(mdfd, SET_ARRAY_INFO, NULL);
853
854                 if (rv) {
855                         fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
856                                 mddev, strerror(errno));
857                         if (must_close) close(mdfd);
858                         return 1;
859                 }
860                 if (ident->bitmap_fd >= 0) {
861                         if (ioctl(mdfd, SET_BITMAP_FILE, ident->bitmap_fd) != 0) {
862                                 fprintf(stderr, Name ": SET_BITMAP_FILE failed.\n");
863                                 if (must_close) close(mdfd);
864                                 return 1;
865                         }
866                 } else if (ident->bitmap_file) {
867                         /* From config file */
868                         int bmfd = open(ident->bitmap_file, O_RDWR);
869                         if (bmfd < 0) {
870                                 fprintf(stderr, Name ": Could not open bitmap file %s\n",
871                                         ident->bitmap_file);
872                                 if (must_close) close(mdfd);
873                                 return 1;
874                         }
875                         if (ioctl(mdfd, SET_BITMAP_FILE, bmfd) != 0) {
876                                 fprintf(stderr, Name ": Failed to set bitmapfile for %s\n", mddev);
877                                 close(bmfd);
878                                 if (must_close) close(mdfd);
879                                 return 1;
880                         }
881                         close(bmfd);
882                 }
883
884                 /* First, add the raid disks, but add the chosen one last */
885                 for (i=0; i<= bestcnt; i++) {
886                         int j;
887                         if (i < bestcnt) {
888                                 j = best[i];
889                                 if (j == chosen_drive)
890                                         continue;
891                         } else
892                                 j = chosen_drive;
893
894                         if (j >= 0 /* && devices[j].uptodate */) {
895                                 mdu_disk_info_t disk;
896                                 memset(&disk, 0, sizeof(disk));
897                                 disk.major = devices[j].major;
898                                 disk.minor = devices[j].minor;
899                                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)!=0) {
900                                         fprintf(stderr, Name ": failed to add %s to %s: %s\n",
901                                                 devices[j].devname,
902                                                 mddev,
903                                                 strerror(errno));
904                                         if (i < info.array.raid_disks || i == bestcnt)
905                                                 okcnt--;
906                                         else
907                                                 sparecnt--;
908                                 } else if (verbose > 0)
909                                         fprintf(stderr, Name ": added %s to %s as %d\n",
910                                                 devices[j].devname, mddev, devices[j].raid_disk);
911                         } else if (verbose > 0 && i < info.array.raid_disks)
912                                 fprintf(stderr, Name ": no uptodate device for slot %d of %s\n",
913                                         i, mddev);
914                 }
915
916                 if (runstop == 1 ||
917                     (runstop <= 0 &&
918                      ( enough(info.array.level, info.array.raid_disks,
919                               info.array.layout, clean, avail, okcnt) &&
920                        (okcnt >= req_cnt || start_partial_ok)
921                              ))) {
922                         if (ioctl(mdfd, RUN_ARRAY, NULL)==0) {
923                                 if (verbose >= 0) {
924                                         fprintf(stderr, Name ": %s has been started with %d drive%s",
925                                                 mddev, okcnt, okcnt==1?"":"s");
926                                         if (okcnt < info.array.raid_disks)
927                                                 fprintf(stderr, " (out of %d)", info.array.raid_disks);
928                                         if (sparecnt)
929                                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
930                                         fprintf(stderr, ".\n");
931                                 }
932                                 if (must_close) {
933                                         int usecs = 1;
934                                         close(mdfd);
935                                         /* There is a nasty race with 'mdadm --monitor'.
936                                          * If it opens this device before we close it,
937                                          * it gets an incomplete open on which IO
938                                          * doesn't work and the capacity if wrong.
939                                          * If we reopen (to check for layered devices)
940                                          * before --monitor closes, we loose.
941                                          *
942                                          * So: wait upto 1 second for there to be
943                                          * a non-zero capacity.
944                                          */
945                                         while (usecs < 1000) {
946                                                 mdfd = open(mddev, O_RDONLY);
947                                                 if (mdfd >= 0) {
948                                                         unsigned long long size;
949                                                         if (get_dev_size(mdfd, NULL, &size) &&
950                                                             size > 0)
951                                                                 break;
952                                                         close(mdfd);
953                                                 }
954                                                 usleep(usecs);
955                                                 usecs <<= 1;
956                                         }
957                                 }
958                                 return 0;
959                         }
960                         fprintf(stderr, Name ": failed to RUN_ARRAY %s: %s\n",
961                                 mddev, strerror(errno));
962
963                         if (!enough(info.array.level, info.array.raid_disks,
964                                     info.array.layout, 1, avail, okcnt))
965                                 fprintf(stderr, Name ": Not enough devices to "
966                                         "start the array.\n");
967                         else if (!enough(info.array.level,
968                                          info.array.raid_disks,
969                                          info.array.layout, clean,
970                                          avail, okcnt))
971                                 fprintf(stderr, Name ": Not enough devices to "
972                                         "start the array while not clean "
973                                         "- consider --force.\n");
974
975                         if (must_close) close(mdfd);
976                         return 1;
977                 }
978                 if (runstop == -1) {
979                         fprintf(stderr, Name ": %s assembled from %d drive%s",
980                                 mddev, okcnt, okcnt==1?"":"s");
981                         if (okcnt != info.array.raid_disks)
982                                 fprintf(stderr, " (out of %d)", info.array.raid_disks);
983                         fprintf(stderr, ", but not started.\n");
984                         if (must_close) close(mdfd);
985                         return 0;
986                 }
987                 if (verbose >= -1) {
988                         fprintf(stderr, Name ": %s assembled from %d drive%s", mddev, okcnt, okcnt==1?"":"s");
989                         if (sparecnt)
990                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
991                         if (!enough(info.array.level, info.array.raid_disks,
992                                     info.array.layout, 1, avail, okcnt))
993                                 fprintf(stderr, " - not enough to start the array.\n");
994                         else if (!enough(info.array.level,
995                                          info.array.raid_disks,
996                                          info.array.layout, clean,
997                                          avail, okcnt))
998                                 fprintf(stderr, " - not enough to start the "
999                                         "array while not clean - consider "
1000                                         "--force.\n");
1001                         else {
1002                                 if (req_cnt == info.array.raid_disks)
1003                                         fprintf(stderr, " - need all %d to start it", req_cnt);
1004                                 else
1005                                         fprintf(stderr, " - need %d of %d to start", req_cnt, info.array.raid_disks);
1006                                 fprintf(stderr, " (use --run to insist).\n");
1007                         }
1008                 }
1009                 if (must_close) close(mdfd);
1010                 return 1;
1011         } else {
1012                 /* The "chosen_drive" is a good choice, and if necessary, the superblock has
1013                  * been updated to point to the current locations of devices.
1014                  * so we can just start the array
1015                  */
1016                 unsigned long dev;
1017                 dev = makedev(devices[chosen_drive].major,
1018                             devices[chosen_drive].minor);
1019                 if (ioctl(mdfd, START_ARRAY, dev)) {
1020                     fprintf(stderr, Name ": Cannot start array: %s\n",
1021                             strerror(errno));
1022                 }
1023
1024         }
1025         if (must_close) close(mdfd);
1026         return 0;
1027 }