2 * mdadm - manage Linux "md" devices aka RAID arrays.
4 * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
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.
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.
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
22 * Email: <neilb@cse.unsw.edu.au>
24 * School of Computer Science and Engineering
25 * The University of New South Wales
34 int Assemble(char *mddev
, int mdfd
,
35 mddev_ident_t ident
, char *conffile
,
37 int readonly
, int runstop
,
39 int verbose
, int force
)
42 * The task of Assemble is to find a collection of
43 * devices that should (according to their superblocks)
44 * form an array, and to give this collection to the MD driver.
45 * In Linux-2.4 and later, this involves submitting a
46 * SET_ARRAY_INFO ioctl with no arg - to prepare
47 * the array - and then submit a number of
48 * ADD_NEW_DISK ioctls to add disks into
49 * the array. Finally RUN_ARRAY might
50 * be submitted to start the array.
52 * Much of the work of Assemble is in finding and/or
53 * checking the disks to make sure they look right.
55 * If mddev is not set, then scan must be and we
56 * read through the config file for dev+uuid mapping
57 * We recurse, setting mddev, for each device that
59 * - has a valid uuid (or any uuid if !uuidset
61 * If mddev is set, we try to determine state of md.
62 * check version - must be at least 0.90.0
63 * check kernel version. must be at least 2.4.
64 * If not, we can possibly fall back on START_ARRAY
65 * Try to GET_ARRAY_INFO.
66 * If possible, give up
67 * If not, try to STOP_ARRAY just to make sure
69 * If !uuidset and scan, look in conf-file for uuid
70 * If not found, give up
71 * If !devlist and scan and uuidset, get list of devs from conf-file
74 * Check superblock - discard if bad
75 * Check uuid (set if we don't have one) - discard if no match
76 * Check superblock similarity if we have a superblock - discard if different
77 * Record events, devicenum, utime
78 * This should give us a list of devices for the array
79 * We should collect the most recent event and utime numbers
81 * Count disks with recent enough event count
82 * While force && !enough disks
83 * Choose newest rejected disks, update event count
84 * mark clean and rewrite superblock
87 * foreach device with recent events : ADD_NEW_DISK
88 * if runstop == 1 || "enough" disks and runstop==0 -> RUN_ARRAY
90 * Check the device numbers in superblock are right
91 * update superblock if any changes
97 mdu_array_info_t array
;
98 mdp_super_t first_super
, super
;
101 unsigned int major
, minor
;
102 unsigned int oldmajor
, oldminor
;
109 int *best
= NULL
; /* indexed by raid_disk */
110 unsigned int bestcnt
= 0;
112 unsigned int okcnt
, sparecnt
;
113 unsigned int req_cnt
;
119 int start_partial_ok
= force
|| devlist
==NULL
;
120 unsigned int num_devs
;
123 vers
= md_get_version(mdfd
);
125 fprintf(stderr
, Name
": %s appears not to be an md device.\n", mddev
);
129 fprintf(stderr
, Name
": Assemble requires driver version 0.90.0 or later.\n"
130 " Upgrade your kernel or try --build\n");
133 if (get_linux_version() < 2004000)
136 if (ioctl(mdfd
, GET_ARRAY_INFO
, &array
)>=0) {
137 fprintf(stderr
, Name
": device %s already active - cannot assemble it\n",
141 ioctl(mdfd
, STOP_ARRAY
, NULL
); /* just incase it was started but has no content */
144 * If any subdevs are listed, then any that don't
145 * match ident are discarded. Remainder must all match and
147 * If no subdevs, then we scan all devices in the config file, but
148 * there must be something in the identity
152 ident
->uuid_set
== 0 &&
153 ident
->super_minor
< 0 &&
154 ident
->devices
== NULL
) {
155 fprintf(stderr
, Name
": No identity information available for %s - cannot assemble.\n",
160 devlist
= conf_get_devs(conffile
);
163 tmpdev
= devlist
; num_devs
= 0;
166 tmpdev
= tmpdev
->next
;
168 best
= malloc(num_devs
* sizeof(*best
));
169 devices
= malloc(num_devs
* sizeof(*devices
));
171 first_super
.md_magic
= 0;
172 for (i
=0; i
<num_devs
; i
++)
176 fprintf(stderr
, Name
": looking for devices for %s\n",
186 devname
= devlist
->devname
;
187 devlist
= devlist
->next
;
189 if (ident
->devices
&&
190 !match_oneof(ident
->devices
, devname
)) {
191 if (inargv
|| verbose
)
192 fprintf(stderr
, Name
": %s is not one of %s\n", devname
, ident
->devices
);
196 dfd
= open(devname
, O_RDONLY
, 0);
198 if (inargv
|| verbose
)
199 fprintf(stderr
, Name
": cannot open device %s: %s\n",
200 devname
, strerror(errno
));
201 } else if (fstat(dfd
, &stb
)< 0) {
203 fprintf(stderr
, Name
": fstat failed for %s: %s\n",
204 devname
, strerror(errno
));
206 } else if ((stb
.st_mode
& S_IFMT
) != S_IFBLK
) {
207 fprintf(stderr
, Name
": %s is not a block device.\n",
210 } else if (load_super(dfd
, &super
)) {
211 if (inargv
|| verbose
)
212 fprintf( stderr
, Name
": no RAID superblock on %s\n",
217 uuid_from_super(this_uuid
, &super
);
221 if (ident
->uuid_set
&&
222 (!havesuper
|| same_uuid(this_uuid
, ident
->uuid
)==0)) {
223 if (inargv
|| verbose
)
224 fprintf(stderr
, Name
": %s has wrong uuid.\n",
228 if (ident
->super_minor
!= UnSet
&&
229 (!havesuper
|| ident
->super_minor
!= super
.md_minor
)) {
230 if (inargv
|| verbose
)
231 fprintf(stderr
, Name
": %s has wrong super-minor.\n",
235 if (ident
->level
!= UnSet
&&
236 (!havesuper
|| ident
->level
!= (int)super
.level
)) {
237 if (inargv
|| verbose
)
238 fprintf(stderr
, Name
": %s has wrong raid level.\n",
242 if (ident
->raid_disks
!= UnSet
&&
243 (!havesuper
|| ident
->raid_disks
!= super
.raid_disks
)) {
244 if (inargv
|| verbose
)
245 fprintf(stderr
, Name
": %s requires wrong number of drives.\n",
250 /* If we are this far, then we are commited to this device.
251 * If the super_block doesn't exist, or doesn't match others,
252 * then we cannot continue
256 fprintf(stderr
, Name
": %s has no superblock - assembly aborted\n",
260 if (compare_super(&first_super
, &super
)) {
261 fprintf(stderr
, Name
": superblock on %s doesn't match others - assembly aborted\n",
267 /* this is needed until we get a more relaxed super block format */
268 if (devcnt
>= MD_SB_DISKS
) {
269 fprintf(stderr
, Name
": ouch - too many devices appear to be in this array. Ignoring %s\n",
274 /* looks like a good enough match to update the super block if needed */
276 if (strcmp(update
, "sparc2.2")==0 ) {
277 /* 2.2 sparc put the events in the wrong place
278 * So we copy the tail of the superblock
279 * up 4 bytes before continuing
281 __u32
*sb32
= (__u32
*)&super
;
282 memcpy(sb32
+MD_SB_GENERIC_CONSTANT_WORDS
+7,
283 sb32
+MD_SB_GENERIC_CONSTANT_WORDS
+7+1,
284 (MD_SB_WORDS
- (MD_SB_GENERIC_CONSTANT_WORDS
+7+1))*4);
285 fprintf (stderr
, Name
": adjusting superblock of %s for 2.2/sparc compatability.\n",
288 if (strcmp(update
, "super-minor") ==0) {
291 super
.md_minor
= MINOR(stb2
.st_rdev
);
293 fprintf(stderr
, Name
": updating superblock of %s with minor number %d\n",
294 devname
, super
.md_minor
);
296 if (strcmp(update
, "summaries") == 0) {
297 /* set nr_disks, active_disks, working_disks,
298 * failed_disks, spare_disks based on disks[]
299 * array in superblock.
300 * Also make sure extra slots aren't 'failed'
302 super
.nr_disks
= super
.active_disks
=
303 super
.working_disks
= super
.failed_disks
=
304 super
.spare_disks
= 0;
305 for (i
=0; i
< MD_SB_DISKS
; i
++)
306 if (super
.disks
[i
].major
||
307 super
.disks
[i
].minor
) {
308 int state
= super
.disks
[i
].state
;
309 if (state
& (1<<MD_DISK_REMOVED
))
312 if (state
& (1<<MD_DISK_ACTIVE
))
313 super
.active_disks
++;
314 if (state
& (1<<MD_DISK_FAULTY
))
315 super
.failed_disks
++;
317 super
.working_disks
++;
320 } else if (i
>= super
.raid_disks
&& super
.disks
[i
].number
== 0)
321 super
.disks
[i
].state
= 0;
323 if (strcmp(update
, "resync") == 0) {
324 /* make sure resync happens */
325 super
.state
&= ~(1<<MD_SB_CLEAN
);
326 super
.recovery_cp
= 0;
328 super
.sb_csum
= calc_sb_csum(&super
);
329 dfd
= open(devname
, O_RDWR
, 0);
331 fprintf(stderr
, Name
": Cannot open %s for superblock update\n",
333 else if (store_super(dfd
, &super
))
334 fprintf(stderr
, Name
": Could not re-write superblock on %s.\n",
341 fprintf(stderr
, Name
": %s is identified as a member of %s, slot %d.\n",
342 devname
, mddev
, super
.this_disk
.raid_disk
);
343 devices
[devcnt
].devname
= devname
;
344 devices
[devcnt
].major
= MAJOR(stb
.st_rdev
);
345 devices
[devcnt
].minor
= MINOR(stb
.st_rdev
);
346 devices
[devcnt
].oldmajor
= super
.this_disk
.major
;
347 devices
[devcnt
].oldminor
= super
.this_disk
.minor
;
348 devices
[devcnt
].events
= md_event(&super
);
349 devices
[devcnt
].utime
= super
.utime
;
350 devices
[devcnt
].raid_disk
= super
.this_disk
.raid_disk
;
351 devices
[devcnt
].uptodate
= 0;
352 devices
[devcnt
].state
= super
.this_disk
.state
;
353 if (most_recent
< devcnt
) {
354 if (devices
[devcnt
].events
355 > devices
[most_recent
].events
)
356 most_recent
= devcnt
;
358 if ((int)super
.level
== -4)
359 /* with multipath, the raid_disk from the superblock is meaningless */
362 i
= devices
[devcnt
].raid_disk
;
365 unsigned int newbestcnt
= i
+10;
366 int *newbest
= malloc(sizeof(int)*newbestcnt
);
368 for (c
=0; c
< newbestcnt
; c
++)
370 newbest
[c
] = best
[c
];
375 bestcnt
= newbestcnt
;
378 || devices
[best
[i
]].events
< devices
[devcnt
].events
)
385 fprintf(stderr
, Name
": no devices found for %s\n",
389 /* now we have some devices that might be suitable.
394 for (i
=0; i
< bestcnt
;i
++) {
396 int event_margin
= !force
;
398 /* note: we ignore error flags in multipath arrays
399 * as they don't make sense
401 if ((int)first_super
.level
!= -4)
402 if (!(devices
[j
].state
& (1<<MD_DISK_SYNC
))) {
403 if (!(devices
[j
].state
& (1<<MD_DISK_FAULTY
)))
407 if (devices
[j
].events
+event_margin
>=
408 devices
[most_recent
].events
) {
409 devices
[j
].uptodate
= 1;
410 if (i
< first_super
.raid_disks
)
416 while (force
&& !enough(first_super
.level
, first_super
.raid_disks
, okcnt
)) {
417 /* Choose the newest best drive which is
418 * not up-to-date, update the superblock
423 for (i
=0; i
<first_super
.raid_disks
&& i
< bestcnt
; i
++) {
426 !devices
[j
].uptodate
&&
427 devices
[j
].events
> 0 &&
429 devices
[j
].events
> devices
[chosen_drive
].events
))
432 if (chosen_drive
< 0)
434 fprintf(stderr
, Name
": forcing event count in %s(%d) from %d upto %d\n",
435 devices
[chosen_drive
].devname
, devices
[chosen_drive
].raid_disk
,
436 (int)(devices
[chosen_drive
].events
),
437 (int)(devices
[most_recent
].events
));
438 fd
= open(devices
[chosen_drive
].devname
, O_RDWR
);
440 fprintf(stderr
, Name
": Couldn't open %s for write - not updating\n",
441 devices
[chosen_drive
].devname
);
442 devices
[chosen_drive
].events
= 0;
445 if (load_super(fd
, &super
)) {
447 fprintf(stderr
, Name
": RAID superblock disappeared from %s - not updating.\n",
448 devices
[chosen_drive
].devname
);
449 devices
[chosen_drive
].events
= 0;
452 super
.events_hi
= (devices
[most_recent
].events
>>32)&0xFFFFFFFF;
453 super
.events_lo
= (devices
[most_recent
].events
)&0xFFFFFFFF;
454 if (super
.level
== 5 || super
.level
== 4) {
455 /* need to force clean */
456 super
.state
= (1<<MD_SB_CLEAN
);
458 super
.sb_csum
= calc_sb_csum(&super
);
459 /*DRYRUN*/ if (store_super(fd
, &super
)) {
461 fprintf(stderr
, Name
": Could not re-write superblock on %s\n",
462 devices
[chosen_drive
].devname
);
463 devices
[chosen_drive
].events
= 0;
467 devices
[chosen_drive
].events
= devices
[most_recent
].events
;
468 devices
[chosen_drive
].uptodate
= 1;
472 /* Now we want to look at the superblock which the kernel will base things on
473 * and compare the devices that we think are working with the devices that the
474 * superblock thinks are working.
475 * If there are differences and --force is given, then update this chosen
479 for (i
=0; chosen_drive
< 0 && i
<bestcnt
; i
++) {
484 if (!devices
[j
].uptodate
)
487 if ((fd
=open(devices
[j
].devname
, O_RDONLY
))< 0) {
488 fprintf(stderr
, Name
": Cannot open %s: %s\n",
489 devices
[j
].devname
, strerror(errno
));
492 if (load_super(fd
, &super
)) {
494 fprintf(stderr
, Name
": RAID superblock has disappeared from %s\n",
501 for (i
=0; i
<bestcnt
; i
++) {
503 unsigned int desired_state
;
505 if (i
< super
.raid_disks
)
506 desired_state
= (1<<MD_DISK_ACTIVE
) | (1<<MD_DISK_SYNC
);
512 if (!devices
[j
].uptodate
)
516 if (devices
[j
].major
!= super
.disks
[i
].major
||
517 devices
[j
].minor
!= super
.disks
[i
].minor
) {
519 super
.disks
[i
].major
= devices
[j
].major
;
520 super
.disks
[i
].minor
= devices
[j
].minor
;
523 if (devices
[j
].oldmajor
!= super
.disks
[i
].major
||
524 devices
[j
].oldminor
!= super
.disks
[i
].minor
) {
526 super
.disks
[i
].major
= devices
[j
].oldmajor
;
527 super
.disks
[i
].minor
= devices
[j
].oldminor
;
529 if (devices
[j
].uptodate
&&
530 (super
.disks
[i
].state
!= desired_state
)) {
532 fprintf(stderr
, Name
": "
533 "clearing FAULTY flag for device %d in %s for %s\n",
534 j
, mddev
, devices
[j
].devname
);
535 super
.disks
[i
].state
= desired_state
;
538 fprintf(stderr
, Name
": "
539 "device %d in %s has wrong state in superblock, but %s seems ok\n",
540 i
, mddev
, devices
[j
].devname
);
543 if (!devices
[j
].uptodate
&&
544 !(super
.disks
[i
].state
& (1 << MD_DISK_FAULTY
))) {
545 fprintf(stderr
, Name
": devices %d of %s is not marked FAULTY in superblock, but cannot be found\n",
549 if (force
&& (super
.level
== 4 || super
.level
== 5) &&
550 okcnt
== super
.raid_disks
-1) {
551 super
.state
= (1<< MD_SB_CLEAN
);
555 if ((force
&& (change
& 2))
556 || (old_linux
&& (change
& 1))) {
558 super
.sb_csum
= calc_sb_csum(&super
);
559 fd
= open(devices
[chosen_drive
].devname
, O_RDWR
);
561 fprintf(stderr
, Name
": Could open %s for write - cannot Assemble array.\n",
562 devices
[chosen_drive
].devname
);
565 if (store_super(fd
, &super
)) {
567 fprintf(stderr
, Name
": Could not re-write superblock on %s\n",
568 devices
[chosen_drive
].devname
);
575 /* count number of in-sync devices according to the superblock.
576 * We must have this number to start the array without -s or -R
579 for (i
=0; i
<MD_SB_DISKS
; i
++)
580 if ((first_super
.disks
[i
].state
& (1<<MD_DISK_SYNC
)) &&
581 (first_super
.disks
[i
].state
& (1<<MD_DISK_ACTIVE
)) &&
582 !(first_super
.disks
[i
].state
& (1<<MD_DISK_FAULTY
)))
586 /* Almost ready to actually *do* something */
588 if (ioctl(mdfd
, SET_ARRAY_INFO
, NULL
) != 0) {
589 fprintf(stderr
, Name
": SET_ARRAY_INFO failed for %s: %s\n",
590 mddev
, strerror(errno
));
593 /* First, add the raid disks, but add the chosen one last */
594 for (i
=0; i
<= bestcnt
; i
++) {
598 if (j
== chosen_drive
)
603 if (j
>= 0 /* && devices[j].uptodate */) {
604 mdu_disk_info_t disk
;
605 memset(&disk
, 0, sizeof(disk
));
606 disk
.major
= devices
[j
].major
;
607 disk
.minor
= devices
[j
].minor
;
608 if (ioctl(mdfd
, ADD_NEW_DISK
, &disk
)!=0) {
609 fprintf(stderr
, Name
": failed to add %s to %s: %s\n",
613 if (i
< first_super
.raid_disks
)
618 fprintf(stderr
, Name
": added %s to %s as %d\n",
619 devices
[j
].devname
, mddev
, devices
[j
].raid_disk
);
620 } else if (verbose
&& i
< first_super
.raid_disks
)
621 fprintf(stderr
, Name
": no uptodate device for slot %d of %s\n",
627 ( enough(first_super
.level
, first_super
.raid_disks
, okcnt
) &&
628 (okcnt
>= req_cnt
|| start_partial_ok
)
630 if (ioctl(mdfd
, RUN_ARRAY
, NULL
)==0) {
631 fprintf(stderr
, Name
": %s has been started with %d drive%s",
632 mddev
, okcnt
, okcnt
==1?"":"s");
633 if (okcnt
< first_super
.raid_disks
)
634 fprintf(stderr
, " (out of %d)", first_super
.raid_disks
);
636 fprintf(stderr
, " and %d spare%s", sparecnt
, sparecnt
==1?"":"s");
637 fprintf(stderr
, ".\n");
640 fprintf(stderr
, Name
": failed to RUN_ARRAY %s: %s\n",
641 mddev
, strerror(errno
));
645 fprintf(stderr
, Name
": %s assembled from %d drive%s, but not started.\n",
646 mddev
, okcnt
, okcnt
==1?"":"s");
649 fprintf(stderr
, Name
": %s assembled from %d drive%s", mddev
, okcnt
, okcnt
==1?"":"s");
651 fprintf(stderr
, " and %d spare%s", sparecnt
, sparecnt
==1?"":"s");
652 if (!enough(first_super
.level
, first_super
.raid_disks
, okcnt
))
653 fprintf(stderr
, " - not enough to start the array.\n");
655 if (req_cnt
== first_super
.raid_disks
)
656 fprintf(stderr
, " - need all %d to start it", req_cnt
);
658 fprintf(stderr
, " - need %d of %d to start", req_cnt
, first_super
.raid_disks
);
659 fprintf(stderr
, " (use --run to insist).\n");
663 /* The "chosen_drive" is a good choice, and if necessary, the superblock has
664 * been updated to point to the current locations of devices.
665 * so we can just start the array
668 dev
= MKDEV(devices
[chosen_drive
].major
,
669 devices
[chosen_drive
].minor
);
670 if (ioctl(mdfd
, START_ARRAY
, dev
)) {
671 fprintf(stderr
, Name
": Cannot start array: %s\n",