Add new mode: --incremental

--incremental allows arrays to be assembled one device at a time.
This is expected to be used with udev.

1 files changed, 197 insertions, 0 deletions

diff --git a/mapfile.c b/mapfile.c
new file mode 100644
index 0000000..746073d
--- /dev/null
+++ b/mapfile.c
@@ -0,0 +1,197 @@
+/*
+ * mapfile - manage /var/run/mdadm.map. Part of:
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2006 Neil Brown <neilb@suse.de>
+ *
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *    Author: Neil Brown
+ *    Email: <neilb@suse.de>
+ *    Paper: Neil Brown
+ *           Novell Inc
+ *           GPO Box Q1283
+ *           QVB Post Office, NSW 1230
+ *           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
+ * also allows the array device name to be easily found.
+ *
+ * The map file is line based with space separated fields.  The fields are:
+ *  Device id  -  mdX or mdpX  where is a number.
+ *  metadata   -  0.90 1.0 1.1 1.2
+ *  UUID       -  uuid of the array
+ *  path       -  path where device created: /dev/md/home
+ *
+ */
+
+
+#include "mdadm.h"
+
+
+int map_write(struct map_ent *mel)
+{
+	FILE *f;
+	int err;
+	int subdir = 1;
+
+	f = fopen("/var/run/mdadm/map.new", "w");
+	if (!f) {
+		f = fopen("/var/run/mdadm.map.new", "w");
+		subdir = 1;
+	}
+	if (!f)
+		return 0;
+	while (mel) {
+		if (mel->devnum < 0)
+			fprintf(f, "mdp%d ", -1-mel->devnum);
+		else
+			fprintf(f, "md%d ", mel->devnum);
+		fprintf(f, "%d.%d ", mel->major, mel->minor);
+		fprintf(f, "%08x:%08x:%08x:%08x ", mel->uuid[0],
+			mel->uuid[1], mel->uuid[2], mel->uuid[3]);
+		fprintf(f, "%s\n", mel->path);
+		mel = mel->next;
+	}
+	fflush(f);
+	err = ferror(f);
+	fclose(f);
+	if (err) {
+		if (subdir)
+			unlink("/var/run/mdadm/map.new");
+		else
+			unlink("/var/run/mdadm.map.new");
+		return 0;
+	}
+	if (subdir)
+		return rename("/var/run/mdadm/map.new",
+			      "/var/run/mdadm/map") == 0;
+	else
+		return rename("/var/run/mdadm.map.new",
+			      "/var/run/mdadm.map") == 0;
+}
+
+void map_add(struct map_ent **melp,
+	    int devnum, int major, int minor, int uuid[4], char *path)
+{
+	struct map_ent *me = malloc(sizeof(*me));
+
+	me->devnum = devnum;
+	me->major = major;
+	me->minor = minor;
+	memcpy(me->uuid, uuid, 16);
+	me->path = strdup(path);
+	me->next = *melp;
+	*melp = me;
+}
+
+void map_read(struct map_ent **melp)
+{
+	FILE *f;
+	char buf[8192];
+	char path[200];
+	int devnum, major, minor, uuid[4];
+	char nam[4];
+
+	*melp = NULL;
+
+	f = fopen("/var/run/mdadm/map", "r");
+	if (!f)
+		f = fopen("/var/run/mdadm.map", "r");
+	if (!f)
+		return;
+
+	while (fgets(buf, sizeof(buf), f)) {
+		if (sscanf(buf, " md%1[p]%d %d.%d %x:%x:%x:%x %200s",
+			   nam, &devnum, &major, &minor, uuid, uuid+1,
+			   uuid+2, uuid+3, path) == 9) {
+			if (nam[0] == 'p')
+				devnum = -1 - devnum;
+			map_add(melp, devnum, major, minor, uuid, path);
+		}
+	}
+	fclose(f);
+}
+
+void map_free(struct map_ent *map)
+{
+	while (map) {
+		struct map_ent *mp = map;
+		map = mp->next;
+		free(mp->path);
+		free(mp);
+	}
+}
+
+int map_update(struct map_ent **mpp, int devnum, int major, int minor,
+	       int *uuid, char *path)
+{
+	struct map_ent *map, *mp;
+	int rv;
+
+	if (mpp && *mpp)
+		map = *mpp;
+	else
+		map_read(&map);
+
+	for (mp = map ; mp ; mp=mp->next)
+		if (mp->devnum == devnum) {
+			mp->major = major;
+			mp->minor = minor;
+			memcpy(mp->uuid, uuid, 16);
+			free(mp->path);
+			mp->path = strdup(path);
+			break;
+		}
+	if (!mp)
+		map_add(&map, devnum, major, minor, uuid, path);
+	*mpp = NULL;
+	rv = map_write(map);
+	map_free(map);
+	return rv;
+}
+
+void map_delete(struct map_ent **mapp, int devnum)
+{
+	struct map_ent *mp;
+
+	if (*mapp == NULL)
+		map_read(mapp);
+
+	for (mp = *mapp; mp; mp = *mapp) {
+		if (mp->devnum == devnum) {
+			*mapp = mp->next;
+			free(mp->path);
+			free(mp);
+		} else
+			mapp = & mp->next;
+	}
+}
+
+struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
+{
+	struct map_ent *mp;
+	if (!*map)
+		map_read(map);
+
+	for (mp = *map ; mp ; mp = mp->next)
+		if (memcmp(uuid, mp->uuid, 16) == 0)
+			return mp;
+	return NULL;
+
+}