]>
git.ipfire.org Git - thirdparty/mdadm.git/blob - mapfile.c
2 * mapfile - manage /var/run/mdadm.map. Part of:
3 * mdadm - manage Linux "md" devices aka RAID arrays.
5 * Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Email: <neilb@suse.de>
27 * QVB Post Office, NSW 1230
31 /* /var/run/mdadm.map is used to track arrays being created in --incremental
32 * more. It particularly allows lookup from UUID to array device, but
33 * also allows the array device name to be easily found.
35 * The map file is line based with space separated fields. The fields are:
36 * Device id - mdX or mdpX where X is a number.
37 * metadata - 0.90 1.0 1.1 1.2 ddf ...
38 * UUID - uuid of the array
39 * path - path where device created: /dev/md/home
41 * The preferred location for the map file is /var/run/mdadm.map.
42 * However /var/run may not exist or be writable in early boot. And if
43 * no-one has created /var/run/mdadm, we still want to survive.
44 * So possible locations are:
45 * /var/run/mdadm/map /var/run/mdadm.map /dev/.mdadm.map
46 * the last, because udev requires a writable /dev very early.
47 * We read from the first one that exists and write to the first
54 #define mapnames(base) { base, base ".new", base ".lock"}
55 char *mapname
[3][3] = {
56 mapnames(VAR_RUN
"/map"),
57 mapnames("/var/run/mdadm.map"),
58 mapnames(ALT_RUN
"/map")
61 int mapmode
[3] = { O_RDONLY
, O_RDWR
|O_CREAT
, O_RDWR
|O_CREAT
| O_TRUNC
};
62 char *mapsmode
[3] = { "r", "w", "w"};
64 FILE *open_map(int modenum
, int *choice
)
67 for (i
= 0 ; i
< 3 ; i
++) {
68 int fd
= open(mapname
[i
][modenum
], mapmode
[modenum
], 0600);
71 return fdopen(fd
, mapsmode
[modenum
]);
77 int map_write(struct map_ent
*mel
)
83 f
= open_map(1, &which
);
87 for (; mel
; mel
= mel
->next
) {
91 fprintf(f
, "mdp%d ", -1-mel
->devnum
);
93 fprintf(f
, "md%d ", mel
->devnum
);
94 fprintf(f
, "%s ", mel
->metadata
);
95 fprintf(f
, "%08x:%08x:%08x:%08x ", mel
->uuid
[0],
96 mel
->uuid
[1], mel
->uuid
[2], mel
->uuid
[3]);
97 fprintf(f
, "%s\n", mel
->path
?:"");
103 unlink(mapname
[which
][1]);
106 return rename(mapname
[which
][1],
107 mapname
[which
][0]) == 0;
111 static FILE *lf
= NULL
;
112 static int lwhich
= 0;
113 int map_lock(struct map_ent
**melp
)
116 lf
= open_map(2, &lwhich
);
119 if (flock(fileno(lf
), LOCK_EX
) != 0) {
131 void map_unlock(struct map_ent
**melp
)
134 flock(fileno(lf
), LOCK_UN
);
137 unlink(mapname
[lwhich
][2]);
141 void map_add(struct map_ent
**melp
,
142 int devnum
, char *metadata
, int uuid
[4], char *path
)
144 struct map_ent
*me
= malloc(sizeof(*me
));
147 strcpy(me
->metadata
, metadata
);
148 memcpy(me
->uuid
, uuid
, 16);
149 me
->path
= path
? strdup(path
) : NULL
;
155 void map_read(struct map_ent
**melp
)
167 f
= open_map(0, &which
);
170 f
= open_map(0, &which
);
175 while (fgets(buf
, sizeof(buf
), f
)) {
177 if (sscanf(buf
, " %3[mdp]%d %s %x:%x:%x:%x %200s",
178 nam
, &devnum
, metadata
, uuid
, uuid
+1,
179 uuid
+2, uuid
+3, path
) >= 7) {
180 if (strncmp(nam
, "md", 2) != 0)
183 devnum
= -1 - devnum
;
184 map_add(melp
, devnum
, metadata
, uuid
, path
);
190 void map_free(struct map_ent
*map
)
193 struct map_ent
*mp
= map
;
200 int map_update(struct map_ent
**mpp
, int devnum
, char *metadata
,
201 int *uuid
, char *path
)
203 struct map_ent
*map
, *mp
;
211 for (mp
= map
; mp
; mp
=mp
->next
)
212 if (mp
->devnum
== devnum
) {
213 strcpy(mp
->metadata
, metadata
);
214 memcpy(mp
->uuid
, uuid
, 16);
216 mp
->path
= path
? strdup(path
) : NULL
;
220 map_add(&map
, devnum
, metadata
, uuid
, path
);
228 void map_delete(struct map_ent
**mapp
, int devnum
)
235 for (mp
= *mapp
; mp
; mp
= *mapp
) {
236 if (mp
->devnum
== devnum
) {
245 struct map_ent
*map_by_uuid(struct map_ent
**map
, int uuid
[4])
251 for (mp
= *map
; mp
; mp
= mp
->next
) {
252 if (memcmp(uuid
, mp
->uuid
, 16) != 0)
254 if (!mddev_busy(mp
->devnum
)) {
263 struct map_ent
*map_by_devnum(struct map_ent
**map
, int devnum
)
269 for (mp
= *map
; mp
; mp
= mp
->next
) {
270 if (mp
->devnum
!= devnum
)
272 if (!mddev_busy(mp
->devnum
)) {
281 struct map_ent
*map_by_name(struct map_ent
**map
, char *name
)
287 for (mp
= *map
; mp
; mp
= mp
->next
) {
290 if (strncmp(mp
->path
, "/dev/md/", 8) != 0)
292 if (strcmp(mp
->path
+8, name
) != 0)
294 if (!mddev_busy(mp
->devnum
)) {
303 /* sets the proper subarray and container_dev according to the metadata
304 * version super_by_fd does this automatically, this routine is meant as
305 * a supplement for guess_super()
307 static void set_member_info(struct supertype
*st
, struct mdstat_ent
*ent
)
310 st
->subarray
[0] = '\0';
312 if (ent
->metadata_version
== NULL
||
313 strncmp(ent
->metadata_version
, "external:", 9) != 0)
316 if (is_subarray(&ent
->metadata_version
[9])) {
317 char version
[strlen(ent
->metadata_version
)+1];
319 char *name
= &version
[10];
321 strcpy(version
, ent
->metadata_version
);
322 subarray
= strrchr(version
, '/');
329 st
->container_dev
= devname2devnum(name
);
330 strncpy(st
->subarray
, subarray
, sizeof(st
->subarray
));
334 void RebuildMap(void)
336 struct mdstat_ent
*mdstat
= mdstat_read(0, 0);
337 struct mdstat_ent
*md
;
338 struct map_ent
*map
= NULL
;
339 int mdp
= get_mdp_major();
340 int require_homehost
;
341 char sys_hostname
[256];
342 char *homehost
= conf_get_homehost(&require_homehost
);
344 if (homehost
== NULL
|| strcmp(homehost
, "<system>")==0) {
345 if (gethostname(sys_hostname
, sizeof(sys_hostname
)) == 0) {
346 sys_hostname
[sizeof(sys_hostname
)-1] = 0;
347 homehost
= sys_hostname
;
351 for (md
= mdstat
; md
; md
= md
->next
) {
352 struct mdinfo
*sra
= sysfs_read(-1, md
->devnum
, GET_DEVS
|SKIP_GONE_DEVS
);
358 for (sd
= sra
->devs
; sd
; sd
= sd
->next
) {
363 struct supertype
*st
;
367 sprintf(dn
, "%d:%d", sd
->disk
.major
, sd
->disk
.minor
);
368 dfd
= dev_open(dn
, O_RDONLY
);
371 st
= guess_super(dfd
);
375 set_member_info(st
, md
);
376 ok
= st
->ss
->load_super(st
, dfd
, NULL
);
381 st
->ss
->getinfo_super(st
, &info
);
383 path
= map_dev(MD_MAJOR
, md
->devnum
, 0);
385 path
= map_dev(mdp
, (-1-md
->devnum
)<< 6, 0);
387 strncmp(path
, "/dev/md/", 8) != 0) {
388 /* We would really like a name that provides
389 * an MD_DEVNAME for udev.
390 * The name needs to be unique both in /dev/md/
391 * and in this mapfile.
392 * It needs to match watch -I or -As would come
395 * Check if array is in mdadm.conf
397 * determine trustworthy from homehost etc
398 * find a unique name based on metadata name.
401 struct mddev_ident_s
*match
= conf_match(&info
, st
);
403 if (match
&& match
->devname
&& match
->devname
[0] == '/') {
404 path
= match
->devname
;
405 if (path
[0] != '/') {
406 strcpy(namebuf
, "/dev/md/");
407 strcat(namebuf
, path
);
415 if ((homehost
== NULL
||
416 st
->ss
->match_home(st
, homehost
) != 1) &&
417 st
->ss
->match_home(st
, "any") != 1 &&
419 || ! conf_name_is_free(info
.name
)))
420 /* require a numeric suffix */
423 /* allow name to be used as-is if no conflict */
428 if (!isdigit(name
[strlen(name
)-1]) &&
434 if (strchr(name
, ':'))
435 /* probably a uniquifying
436 * hostname prefix. Allow
443 sprintf(namebuf
, "/dev/md/%s%s%d",
446 sprintf(namebuf
, "/dev/md/%s",
449 if (lstat(namebuf
, &stb
) != 0 &&
451 !map_by_name(&map
, namebuf
+8)))
457 map_add(&map
, md
->devnum
,
460 st
->ss
->free_super(st
);
467 for (md
= mdstat
; md
; md
= md
->next
) {
468 struct mdinfo
*sra
= sysfs_read(-1, md
->devnum
, GET_VERSION
);
469 sysfs_uevent(sra
, "change");