/*
- * mapfile - manage /var/run/mdadm.map. Part of:
+ * mapfile - keep track of uuid <-> array mapping. Part of:
* mdadm - manage Linux "md" devices aka RAID arrays.
*
- * Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
+ * Copyright (C) 2006-2010 Neil Brown <neilb@suse.de>
*
*
* This program is free software; you can redistribute it and/or modify
* Australia
*/
-/* /var/run/mdadm.map is used to track arrays being created in --incremental
- * more. It particularly allows lookup from UUID to array device, but
+/* The mapfile is used to track arrays being created in --incremental
+ * mode. It particularly allows lookup from UUID to array device, but
* also allows the array device name to be easily found.
*
* The map file is line based with space separated fields. The fields are:
* UUID - uuid of the array
* path - path where device created: /dev/md/home
*
- * The preferred location for the map file is /var/run/mdadm.map.
- * However /var/run may not exist or be writable in early boot. And if
- * no-one has created /var/run/mdadm, we still want to survive.
- * So possible locations are:
- * /var/run/mdadm/map /var/run/mdadm.map /dev/.mdadm.map
- * the last, because udev requires a writable /dev very early.
- * We read from the first one that exists and write to the first
- * one that we can.
+ * The best place for the mapfile wold be /var/run/mdadm/map. However
+ * it is needed during initramfs early-boot, and /var/run doesn't exist there
+ * and certainly doesn't persist through to normal boot.
+ * So we store it in /dev/.mdadm/map but allow this to be changed at
+ * compile time. via MAP_DIR and MAP_FILE
+ *
*/
#include "mdadm.h"
+#include <sys/file.h>
#include <ctype.h>
-#define mapnames(base) { #base, #base ".new", #base ".lock"}
-char *mapname[3][3] = {
- mapnames(/var/run/mdadm/map),
- mapnames(/var/run/mdadm.map),
- mapnames(/dev/.mdadm.map)
+#ifndef MAP_DIR
+#define MAP_DIR "/dev/.mdadm"
+#define MAP_FILE "map"
+#endif
+
+#define MAP_READ 0
+#define MAP_NEW 1
+#define MAP_LOCK 2
+#define MAP_DIRNAME 3
+#define mapnames(dir, base) { \
+
+char *mapname[4] = {
+ MAP_DIR "/" MAP_FILE,
+ MAP_DIR "/" MAP_FILE ".new",
+ MAP_DIR "/" MAP_FILE ".lock",
+ MAP_DIR
};
-int mapmode[3] = { O_RDONLY, O_RDWR|O_CREAT, O_RDWR|O_CREAT | O_TRUNC };
+int mapmode[3] = { O_RDONLY, O_RDWR|O_CREAT, O_RDWR|O_CREAT|O_TRUNC };
char *mapsmode[3] = { "r", "w", "w"};
-FILE *open_map(int modenum, int *choice)
+FILE *open_map(int modenum)
{
- int i;
- for (i = 0 ; i < 3 ; i++) {
- int fd = open(mapname[i][modenum], mapmode[modenum], 0600);
- if (fd >= 0) {
- *choice = i;
- return fdopen(fd, mapsmode[modenum]);
- }
- }
+ int fd;
+ if ((mapmode[modenum] & O_CREAT))
+ /* Attempt to create directory, don't worry about
+ * failure.
+ */
+ (void)mkdir(mapname[MAP_DIRNAME], 0755);
+ fd = open(mapname[modenum], mapmode[modenum], 0600);
+ if (fd >= 0)
+ return fdopen(fd, mapsmode[modenum]);
return NULL;
}
{
FILE *f;
int err;
- int which;
- f = open_map(1, &which);
+ f = open_map(MAP_NEW);
if (!f)
return 0;
err = ferror(f);
fclose(f);
if (err) {
- unlink(mapname[which][1]);
+ unlink(mapname[1]);
return 0;
}
- return rename(mapname[which][1],
- mapname[which][0]) == 0;
+ return rename(mapname[1],
+ mapname[0]) == 0;
}
static FILE *lf = NULL;
-static int lwhich = 0;
int map_lock(struct map_ent **melp)
{
- if (lf == NULL) {
- lf = open_map(2, &lwhich);
+ while (lf == NULL) {
+ struct stat buf;
+ lf = open_map(MAP_LOCK);
if (lf == NULL)
return -1;
- if (lockf(fileno(lf), F_LOCK, 0) != 0) {
+ if (flock(fileno(lf), LOCK_EX) != 0) {
fclose(lf);
lf = NULL;
return -1;
}
+ if (fstat(fileno(lf), &buf) != 0 ||
+ buf.st_nlink == 0) {
+ /* The owner of the lock unlinked it,
+ * so we have a lock on a stale file,
+ * try again
+ */
+ fclose(lf);
+ lf = NULL;
+ }
}
if (*melp)
map_free(*melp);
void map_unlock(struct map_ent **melp)
{
- if (lf)
+ if (lf) {
+ /* must unlink before closing the file,
+ * as only the owner of the lock may
+ * unlink the file
+ */
+ unlink(mapname[2]);
fclose(lf);
- unlink(mapname[lwhich][2]);
+ }
lf = NULL;
}
int devnum, uuid[4];
char metadata[30];
char nam[4];
- int which;
*melp = NULL;
- f = open_map(0, &which);
+ f = open_map(MAP_READ);
if (!f) {
RebuildMap();
- f = open_map(0, &which);
+ f = open_map(MAP_READ);
}
if (!f)
return;
}
}
+void map_remove(struct map_ent **mapp, int devnum)
+{
+ if (devnum == NoMdDev)
+ return;
+
+ map_delete(mapp, devnum);
+ map_write(*mapp);
+ map_free(*mapp);
+}
+
struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
{
struct map_ent *mp;
* version super_by_fd does this automatically, this routine is meant as
* a supplement for guess_super()
*/
-static void set_member_info(struct supertype *st, struct mdstat_ent *ent)
+static char *get_member_info(struct mdstat_ent *ent)
{
- st->subarray[0] = '\0';
-
if (ent->metadata_version == NULL ||
strncmp(ent->metadata_version, "external:", 9) != 0)
- return;
+ return NULL;
if (is_subarray(&ent->metadata_version[9])) {
- char version[strlen(ent->metadata_version)+1];
char *subarray;
- char *name = &version[10];
- strcpy(version, ent->metadata_version);
- subarray = strrchr(version, '/');
- name = &version[10];
-
- if (!subarray)
- return;
- *subarray++ = '\0';
-
- st->container_dev = devname2devnum(name);
- strncpy(st->subarray, subarray, sizeof(st->subarray));
+ subarray = strrchr(ent->metadata_version, '/');
+ return subarray + 1;
}
+ return NULL;
}
void RebuildMap(void)
}
for (md = mdstat ; md ; md = md->next) {
- struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_DEVS|SKIP_GONE_DEVS);
+ struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_DEVS);
struct mdinfo *sd;
if (!sra)
int dfd;
int ok;
struct supertype *st;
+ char *subarray;
char *path;
- struct mdinfo info;
+ struct mdinfo *info;
sprintf(dn, "%d:%d", sd->disk.major, sd->disk.minor);
dfd = dev_open(dn, O_RDONLY);
if ( st == NULL)
ok = -1;
else {
- set_member_info(st, md);
+ subarray = get_member_info(md);
ok = st->ss->load_super(st, dfd, NULL);
}
close(dfd);
if (ok != 0)
continue;
- st->ss->getinfo_super(st, &info);
+ info = st->ss->container_content(st, subarray);
+
if (md->devnum >= 0)
path = map_dev(MD_MAJOR, md->devnum, 0);
else
* find a unique name based on metadata name.
*
*/
- struct mddev_ident_s *match = conf_match(&info, st);
+ struct mddev_ident_s *match = conf_match(info, st);
struct stat stb;
if (match && match->devname && match->devname[0] == '/') {
path = match->devname;
st->ss->match_home(st, homehost) != 1) &&
st->ss->match_home(st, "any") != 1 &&
(require_homehost
- || ! conf_name_is_free(info.name)))
+ || ! conf_name_is_free(info->name)))
/* require a numeric suffix */
unum = 0;
else
/* allow name to be used as-is if no conflict */
unum = -1;
- name = info.name;
+ name = info->name;
if (!*name) {
name = st->ss->name;
if (!isdigit(name[strlen(name)-1]) &&
}
}
map_add(&map, md->devnum,
- info.text_version,
- info.uuid, path);
+ info->text_version,
+ info->uuid, path);
st->ss->free_super(st);
+ free(info);
break;
}
sysfs_free(sra);
}
- map_write(map);
+ /* Only trigger a change if we wrote a new map file */
+ if (map_write(map))
+ for (md = mdstat ; md ; md = md->next) {
+ struct mdinfo *sra = sysfs_read(-1, md->devnum,
+ GET_VERSION);
+ if (sra)
+ sysfs_uevent(sra, "change");
+ sysfs_free(sra);
+ }
map_free(map);
- for (md = mdstat ; md ; md = md->next) {
- struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_VERSION);
- sysfs_uevent(sra, "change");
- sysfs_free(sra);
- }
free_mdstat(mdstat);
}
projects / thirdparty / mdadm.git / blobdiff