/*
- * 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
+/* 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.
*
* 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 /lib/initrw/madam/map
- * The last can easily be change at compile to e.g. somewhere in /dev.
- * 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 "/map"),
- mapnames("/var/run/mdadm.map"),
- mapnames(ALT_RUN "/" ALT_MAPFILE)
+#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
};
-char *mapdir[3] = { VAR_RUN, NULL, ALT_RUN };
-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;
- if ((mapmode[modenum] & O_CREAT) &&
- mapdir[modenum])
- /* Attempt to create directory, don't worry about
- * failure.
- */
- mkdir(mapdir[modenum], 0755);
- 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 (flock(fileno(lf), LOCK_EX) != 0) {
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) {
- flock(fileno(lf), LOCK_UN);
+ /* 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;
}
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)
for (md = mdstat ; md ; md = md->next) {
struct mdinfo *sra = sysfs_read(-1, md->devnum,
GET_VERSION);
- sysfs_uevent(sra, "change");
+ if (sra)
+ sysfs_uevent(sra, "change");
sysfs_free(sra);
}
map_free(map);
projects / thirdparty / mdadm.git / blobdiff