Discard devnum in favour of devnm

We widely use a "devnum" which is 0 or +ve for md%d devices
and -ve for md_d%d devices.
But I want to be able to use md_%s device names.

So get rid of devnum (a number) and use devnm (a 32char string).
eg.
  md0
  md_d2
  md_home

Signed-off-by: NeilBrown <neilb@suse.de>

29 files changed, 652 insertions, 710 deletions

diff --git a/Assemble.c b/Assemble.c
index eed1c9b0..ab7e249e 100644
--- a/Assemble.c
+++ b/Assemble.c
@@ -217,7 +217,7 @@ static int select_devices(struct mddev_dev *devlist,
 					       devname);
 				tmpdev->used = 2;
 			} else if (auto_assem &&
-				   !conf_test_metadata(tst->ss->name, (pol = devnum_policy(stb.st_rdev)),
+				   !conf_test_metadata(tst->ss->name, (pol = devid_policy(stb.st_rdev)),
 						       tst->ss->match_home(tst, c->homehost) == 1)) {
 				if (report_mismatch)
 					pr_err("%s has metadata type %s for which "
@@ -243,7 +243,7 @@ static int select_devices(struct mddev_dev *devlist,
 					       tst->ss->name, devname);
 				tmpdev->used = 2;
 			} else if (auto_assem && st == NULL &&
-				   !conf_test_metadata(tst->ss->name, (pol = devnum_policy(stb.st_rdev)),
+				   !conf_test_metadata(tst->ss->name, (pol = devid_policy(stb.st_rdev)),
 						       tst->ss->match_home(tst, c->homehost) == 1)) {
 				if (report_mismatch)
 					pr_err("%s has metadata type %s for which "
@@ -469,7 +469,7 @@ static int select_devices(struct mddev_dev *devlist,
 		/* Collect domain information from members only */
 		if (tmpdev && tmpdev->used == 1) {
 			if (!pol)
-				pol = devnum_policy(stb.st_rdev);
+				pol = devid_policy(stb.st_rdev);
 			domain_merge(&domains, pol, tst?tst->ss->name:NULL);
 		}
 		dev_policy_free(pol);
@@ -510,7 +510,7 @@ static int select_devices(struct mddev_dev *devlist,
 			       tmpdev->devname, strerror(errno));
 			tmpdev->used = 2;
 		} else {
-			struct dev_policy *pol = devnum_policy(stb.st_rdev);
+			struct dev_policy *pol = devid_policy(stb.st_rdev);
 			int dt = domain_test(domains, pol, NULL);
 			if (inargv && dt != 0)
 				/* take this spare as domains match
@@ -1032,7 +1032,7 @@ static int start_array(int mdfd,
 				 * of the stripe cache - default is 256
 				 */
 				if (256 < 4 * (content->array.chunk_size/4096)) {
-					struct mdinfo *sra = sysfs_read(mdfd, 0, 0);
+					struct mdinfo *sra = sysfs_read(mdfd, NULL, 0);
 					if (sra)
 						sysfs_set_num(sra, NULL,
 							      "stripe_cache_size",
@@ -1269,7 +1269,7 @@ try_again:
 	if (mp) {
 		struct mdinfo *dv;
 		/* array already exists. */
-		pre_exist = sysfs_read(-1, mp->devnum, GET_LEVEL|GET_DEVS);
+		pre_exist = sysfs_read(-1, mp->devnm, GET_LEVEL|GET_DEVS);
 		if (pre_exist->array.level != UnSet) {
 			pr_err("Found some drive for an array that is already active: %s\n",
 			       mp->path);
@@ -1302,7 +1302,7 @@ try_again:
 		    strcmp(mddev, chosen_name) != 0)
 			pr_err("Merging with already-assembled %s\n",
 			       chosen_name);
-		mdfd = open_dev_excl(mp->devnum);
+		mdfd = open_dev_excl(mp->devnm);
 	} else {
 		int trustworthy = FOREIGN;
 		name = content->name;
@@ -1359,7 +1359,7 @@ try_again:
 		return 1;
 	}
 	if (pre_exist == NULL) {
-		if (mddev_busy(fd2devnum(mdfd))) {
+		if (mddev_busy(fd2devnm(mdfd))) {
 			pr_err("%s already active, cannot restart it!\n",
 			       mddev);
 			for (tmpdev = devlist ;
@@ -1526,7 +1526,7 @@ try_again:
 	}
 	st->ss->getinfo_super(st, content, NULL);
 #ifndef MDASSEMBLE
-	sysfs_init(content, mdfd, 0);
+	sysfs_init(content, mdfd, NULL);
 #endif
 	for (i=0; i<bestcnt; i++) {
 		int j = best[i];
@@ -1665,7 +1665,7 @@ try_again:
 	/* First, fill in the map, so that udev can find our name
 	 * as soon as we become active.
 	 */
-	map_update(&map, fd2devnum(mdfd), content->text_version,
+	map_update(&map, fd2devnm(mdfd), content->text_version,
 		   content->uuid, chosen_name);
 
 	rv = start_array(mdfd, mddev, content,
@@ -1726,9 +1726,9 @@ int assemble_container_content(struct supertype *st, int mdfd,
 	int old_raid_disks;
 	int start_reshape;
 
-	sysfs_init(content, mdfd, 0);
+	sysfs_init(content, mdfd, NULL);
 
-	sra = sysfs_read(mdfd, 0, GET_VERSION);
+	sra = sysfs_read(mdfd, NULL, GET_VERSION);
 	if (sra == NULL || strcmp(sra->text_version, content->text_version) != 0) {
 		if (content->array.major_version == -1 &&
 		    content->array.minor_version == -2 &&
@@ -1770,7 +1770,7 @@ int assemble_container_content(struct supertype *st, int mdfd,
 	if (working + expansion == 0)
 		return 1;/* Nothing new, don't try to start */
 
-	map_update(&map, fd2devnum(mdfd),
+	map_update(&map, fd2devnm(mdfd),
 		   content->text_version,
 		   content->uuid, chosen_name);
 
@@ -1792,10 +1792,10 @@ int assemble_container_content(struct supertype *st, int mdfd,
 				return 1;
 
 			if (st->ss->external) {
-				if (!mdmon_running(st->container_dev))
-					start_mdmon(st->container_dev);
-				ping_monitor_by_id(st->container_dev);
-				if (mdmon_running(st->container_dev) &&
+				if (!mdmon_running(st->container_devnm))
+					start_mdmon(st->container_devnm);
+				ping_monitor(st->container_devnm);
+				if (mdmon_running(st->container_devnm) &&
 				    st->update_tail == NULL)
 					st->update_tail = &st->updates;
 			}
@@ -1814,9 +1814,9 @@ int assemble_container_content(struct supertype *st, int mdfd,
 						    "readonly");
 				/* start mdmon if needed. */
 				if (!err) {
-					if (!mdmon_running(st->container_dev))
-						start_mdmon(st->container_dev);
-					ping_monitor_by_id(st->container_dev);
+					if (!mdmon_running(st->container_devnm))
+						start_mdmon(st->container_devnm);
+					ping_monitor(st->container_devnm);
 				}
 				break;
 			}
diff --git a/Build.c b/Build.c
index 1887822c..5c97d630 100644
--- a/Build.c
+++ b/Build.c
@@ -115,7 +115,7 @@ int Build(char *mddev, struct mddev_dev *devlist,
 	}
 	mddev = chosen_name;
 
-	map_update(&map, fd2devnum(mdfd), "none", uuid, chosen_name);
+	map_update(&map, fd2devnm(mdfd), "none", uuid, chosen_name);
 	map_unlock(&map);
 
 	vers = md_get_version(mdfd);
diff --git a/Create.c b/Create.c
index 436bd1d9..a4aab41f 100644
--- a/Create.c
+++ b/Create.c
@@ -703,31 +703,31 @@ int Create(struct supertype *st, char *mddev,
 
 	total_slots = info.array.nr_disks;
 	st->ss->getinfo_super(st, &info, NULL);
-	sysfs_init(&info, mdfd, 0);
+	sysfs_init(&info, mdfd, NULL);
 
 	if (did_default && c->verbose >= 0) {
 		if (is_subarray(info.text_version)) {
-			int dnum = devname2devnum(info.text_version+1);
-			char *path;
-			int mdp = get_mdp_major();
+			char devnm[32];
+			char *ep;
 			struct mdinfo *mdi;
-			if (dnum > 0)
-				path = map_dev(MD_MAJOR, dnum, 1);
-			else
-				path = map_dev(mdp, (-1-dnum)<< 6, 1);
 
-			mdi = sysfs_read(-1, dnum, GET_VERSION);
+			strncpy(devnm, info.text_version+1, 32);
+			devnm[31] = 0;
+			ep = strchr(devnm, '/');
+			if (ep)
+				*ep = 0;
+
+			mdi = sysfs_read(-1, devnm, GET_VERSION);
 
-			pr_err("Creating array inside "
-				"%s container %s\n",
-				mdi?mdi->text_version:"managed", path);
+			pr_err("Creating array inside %s container %s\n",
+				mdi?mdi->text_version:"managed", devnm);
 			sysfs_free(mdi);
 		} else
 			pr_err("Defaulting to version"
 				" %s metadata\n", info.text_version);
 	}
 
-	map_update(&map, fd2devnum(mdfd), info.text_version,
+	map_update(&map, fd2devnm(mdfd), info.text_version,
 		   info.uuid, chosen_name);
 	map_unlock(&map);
 
@@ -758,9 +758,9 @@ int Create(struct supertype *st, char *mddev,
 		s->bitmap_file = NULL;
 	}
 
-	sysfs_init(&info, mdfd, 0);
+	sysfs_init(&info, mdfd, NULL);
 
-	if (st->ss->external && st->container_dev != NoMdDev) {
+	if (st->ss->external && st->container_devnm[0]) {
 		/* member */
 
 		/* When creating a member, we need to be careful
@@ -775,17 +775,17 @@ int Create(struct supertype *st, char *mddev,
 		 *
 		 * For now, fail if it is already running.
 		 */
-		container_fd = open_dev_excl(st->container_dev);
+		container_fd = open_dev_excl(st->container_devnm);
 		if (container_fd < 0) {
 			pr_err("Cannot get exclusive "
 				"open on container - weird.\n");
 			goto abort;
 		}
-		if (mdmon_running(st->container_dev)) {
+		if (mdmon_running(st->container_devnm)) {
 			if (c->verbose)
 				pr_err("reusing mdmon "
 					"for %s.\n",
-					devnum2devname(st->container_dev));
+					st->container_devnm);
 			st->update_tail = &st->updates;
 		} else
 			need_mdmon = 1;
@@ -864,7 +864,7 @@ int Create(struct supertype *st, char *mddev,
 					fd = -1;
 				else {
 					if (st->ss->external &&
-					    st->container_dev != NoMdDev)
+					    st->container_devnm[0])
 						fd = open(dv->devname, O_RDWR);
 					else
 						fd = open(dv->devname, O_RDWR|O_EXCL);
@@ -932,10 +932,10 @@ int Create(struct supertype *st, char *mddev,
 			st->ss->getinfo_super(st, &info_new, NULL);
 			if (st->ss->external && s->level != LEVEL_CONTAINER &&
 			    !same_uuid(info_new.uuid, info.uuid, 0)) {
-				map_update(&map, fd2devnum(mdfd),
+				map_update(&map, fd2devnm(mdfd),
 					   info_new.text_version,
 					   info_new.uuid, chosen_name);
-				me = map_by_devnum(&map, st->container_dev);
+				me = map_by_devnm(&map, st->container_devnm);
 			}
 
 			if (st->ss->write_init_super(st)) {
@@ -948,7 +948,7 @@ int Create(struct supertype *st, char *mddev,
 				char *path = xstrdup(me->path);
 
 				st->ss->getinfo_super(st, &info_new, NULL);
-				map_update(&map, st->container_dev,
+				map_update(&map, st->container_devnm,
 					   info_new.text_version,
 					   info_new.uuid, path);
 				free(path);
@@ -1019,11 +1019,11 @@ int Create(struct supertype *st, char *mddev,
 		}
 		if (c->verbose >= 0)
 			pr_err("array %s started.\n", mddev);
-		if (st->ss->external && st->container_dev != NoMdDev) {
+		if (st->ss->external && st->container_devnm[0]) {
 			if (need_mdmon)
-				start_mdmon(st->container_dev);
+				start_mdmon(st->container_devnm);
 
-			ping_monitor_by_id(st->container_dev);
+			ping_monitor(st->container_devnm);
 			close(container_fd);
 		}
 		wait_for(chosen_name, mdfd);
@@ -1036,7 +1036,7 @@ int Create(struct supertype *st, char *mddev,
  abort:
 	map_lock(&map);
  abort_locked:
-	map_remove(&map, fd2devnum(mdfd));
+	map_remove(&map, fd2devnm(mdfd));
 	map_unlock(&map);
 
 	if (mdfd >= 0)
diff --git a/Detail.c b/Detail.c
index ab49803d..250d5864 100644
--- a/Detail.c
+++ b/Detail.c
@@ -88,7 +88,7 @@ int Detail(char *dev, struct context *c)
 		close(fd);
 		return rv;
 	}
-	sra = sysfs_read(fd, 0, GET_VERSION);
+	sra = sysfs_read(fd, NULL, GET_VERSION);
 	st = super_by_fd(fd, &subarray);
 
 	if (fstat(fd, &stb) != 0 && !S_ISBLK(stb.st_mode))
@@ -102,10 +102,11 @@ int Detail(char *dev, struct context *c)
 		/* This is a subarray of some container.
 		 * We want the name of the container, and the member
 		 */
-		int dn = st->container_dev;
+		int devid = devnm2devid(st->container_devnm);
 
 		member = subarray;
-		container = map_dev_preferred(dev2major(dn), dev2minor(dn), 1, c->prefer);
+		container = map_dev_preferred(major(devid), minor(devid),
+					      1, c->prefer);
 	}
 
 	/* try to load a superblock */
@@ -217,7 +218,7 @@ int Detail(char *dev, struct context *c)
 		} else {
 			struct map_ent *mp, *map = NULL;
 			char nbuf[64];
-			mp = map_by_devnum(&map, fd2devnum(fd));
+			mp = map_by_devnm(&map, fd2devnm(fd));
 			if (mp) {
 				__fname_from_uuid(mp->uuid, 0, nbuf, ':');
 				printf("MD_UUID=%s\n", nbuf+5);
@@ -306,12 +307,11 @@ int Detail(char *dev, struct context *c)
 		unsigned long long larray_size;
 		struct mdstat_ent *ms = mdstat_read(0, 0);
 		struct mdstat_ent *e;
-		int devnum = array.md_minor;
-		if (major(stb.st_rdev) == (unsigned)get_mdp_major())
-			devnum = -1 - devnum;
+		char *devnm;
 
+		devnm = stat2devnm(&stb);
 		for (e=ms; e; e=e->next)
-			if (e->devnum == devnum)
+			if (strcmp(e->devnm, devnm) == 0)
 				break;
 		if (!get_dev_size(fd, NULL, &larray_size))
 			larray_size = 0;
@@ -498,7 +498,7 @@ This is pretty boring
 				char path[200];
 				char vbuf[1024];
 				int nlen = strlen(sra->sys_name);
-				int dn;
+				int devid;
 				if (de->d_name[0] == '.')
 					continue;
 				sprintf(path, "/sys/block/%s/md/metadata_version",
@@ -510,10 +510,10 @@ This is pretty boring
 				    strncmp(vbuf+10, sra->sys_name, nlen) != 0 ||
 				    vbuf[10+nlen] != '/')
 					continue;
-				dn = devname2devnum(de->d_name);
+				devid = devnm2devid(de->d_name);
 				printf(" %s", map_dev_preferred(
-					       dev2major(dn),
-					       dev2minor(dn), 1, c->prefer));
+					       major(devid),
+					       minor(devid), 1, c->prefer));
 			}
 			if (dir)
 				closedir(dir);
diff --git a/Grow.c b/Grow.c
index 2cc93578..948fc8d9 100644
--- a/Grow.c
+++ b/Grow.c
@@ -382,7 +382,7 @@ int Grow_addbitmap(char *devname, int fd, struct context *c, struct shape *s)
 				"with %s metadata\n", st->ss->name);
 			return 1;
 		}
-		mdi = sysfs_read(fd, -1, GET_BITMAP_LOCATION);
+		mdi = sysfs_read(fd, NULL, GET_BITMAP_LOCATION);
 		if (mdi)
 			offset_setable = 1;
 		for (d=0; d< st->max_devs; d++) {
@@ -421,7 +421,7 @@ int Grow_addbitmap(char *devname, int fd, struct context *c, struct shape *s)
 		}
 		if (offset_setable) {
 			st->ss->getinfo_super(st, mdi, NULL);
-			sysfs_init(mdi, fd, -1);
+			sysfs_init(mdi, fd, NULL);
 			rv = sysfs_set_num_signed(mdi, NULL, "bitmap/location",
 						  mdi->bitmap_offset);
 		} else {
@@ -533,13 +533,11 @@ static int check_idle(struct supertype *st)
 	/* Check that all member arrays for this container, or the
 	 * container of this array, are idle
 	 */
-	int container_dev = (st->container_dev != NoMdDev
-			     ? st->container_dev : st->devnum);
-	char container[40];
+	char *container = (st->container_devnm[0]
+			   ? st->container_devnm : st->devnm);
 	struct mdstat_ent *ent, *e;
 	int is_idle = 1;
 
-	fmt_devname(container, container_dev);
 	ent = mdstat_read(0, 0);
 	for (e = ent ; e; e = e->next) {
 		if (!is_container_member(e, container))
@@ -555,15 +553,12 @@ static int check_idle(struct supertype *st)
 
 static int freeze_container(struct supertype *st)
 {
-	int container_dev = (st->container_dev != NoMdDev
-			     ? st->container_dev : st->devnum);
-	char container[40];
+	char *container = (st->container_devnm[0]
+			   ? st->container_devnm : st->devnm);
 
 	if (!check_idle(st))
 		return -1;
 
-	fmt_devname(container, container_dev);
-
 	if (block_monitor(container, 1)) {
 		pr_err("failed to freeze container\n");
 		return -2;
@@ -574,11 +569,8 @@ static int freeze_container(struct supertype *st)
 
 static void unfreeze_container(struct supertype *st)
 {
-	int container_dev = (st->container_dev != NoMdDev
-			     ? st->container_dev : st->devnum);
-	char container[40];
-
-	fmt_devname(container, container_dev);
+	char *container = (st->container_devnm[0]
+			   ? st->container_devnm : st->devnm);
 
 	unblock_monitor(container, 1);
 }
@@ -594,7 +586,7 @@ static int freeze(struct supertype *st)
 	if (st->ss->external)
 		return freeze_container(st);
 	else {
-		struct mdinfo *sra = sysfs_read(-1, st->devnum, GET_VERSION);
+		struct mdinfo *sra = sysfs_read(-1, st->devnm, GET_VERSION);
 		int err;
 		char buf[20];
 
@@ -616,7 +608,7 @@ static void unfreeze(struct supertype *st)
 	if (st->ss->external)
 		return unfreeze_container(st);
 	else {
-		struct mdinfo *sra = sysfs_read(-1, st->devnum, GET_VERSION);
+		struct mdinfo *sra = sysfs_read(-1, st->devnm, GET_VERSION);
 
 		if (sra)
 			sysfs_set_str(sra, NULL, "sync_action", "idle");
@@ -1541,7 +1533,6 @@ int Grow_reshape(char *devname, int fd,
 	int frozen;
 	int changed = 0;
 	char *container = NULL;
-	char container_buf[20];
 	int cfd = -1;
 
 	struct mddev_dev *dv;
@@ -1594,16 +1585,15 @@ int Grow_reshape(char *devname, int fd,
 	 * pre-requisite spare devices (mdmon owns final validation)
 	 */
 	if (st->ss->external) {
-		int container_dev;
 		int rv;
 
 		if (subarray) {
-			container_dev = st->container_dev;
-			cfd = open_dev_excl(st->container_dev);
+			container = st->container_devnm;
+			cfd = open_dev_excl(st->container_devnm);
 		} else {
-			container_dev = st->devnum;
+			container = st->devnm;
 			close(fd);
-			cfd = open_dev_excl(st->devnum);
+			cfd = open_dev_excl(st->devnm);
 			fd = cfd;
 		}
 		if (cfd < 0) {
@@ -1613,9 +1603,6 @@ int Grow_reshape(char *devname, int fd,
 			return 1;
 		}
 
-		fmt_devname(container_buf, container_dev);
-		container = container_buf;
-
 		rv = st->ss->load_container(st, cfd, NULL);
 
 		if (rv) {
@@ -1646,7 +1633,7 @@ int Grow_reshape(char *devname, int fd,
 					pr_err("cannot reshape arrays in"
 					       " container with unsupported"
 					       " metadata: %s(%s)\n",
-					       devname, container_buf);
+					       devname, container);
 					sysfs_free(cc);
 					free(subarray);
 					return 1;
@@ -1654,7 +1641,7 @@ int Grow_reshape(char *devname, int fd,
 			}
 			sysfs_free(cc);
 		}
-		if (mdmon_running(container_dev))
+		if (mdmon_running(container))
 			st->update_tail = &st->updates;
 	}
 
@@ -1673,7 +1660,7 @@ int Grow_reshape(char *devname, int fd,
 		return 1;
 	}
 
-	sra = sysfs_read(fd, 0, GET_LEVEL | GET_DISKS | GET_DEVS
+	sra = sysfs_read(fd, NULL, GET_LEVEL | GET_DISKS | GET_DEVS
 			 | GET_STATE | GET_VERSION);
 	if (sra) {
 		if (st->ss->external && subarray == NULL) {
@@ -1803,10 +1790,10 @@ int Grow_reshape(char *devname, int fd,
 			}
 			/* make sure mdmon is
 			 * aware of the new level */
-			if (!mdmon_running(st->container_dev))
-				start_mdmon(st->container_dev);
+			if (!mdmon_running(st->container_devnm))
+				start_mdmon(st->container_devnm);
 			ping_monitor(container);
-			if (mdmon_running(st->container_dev) &&
+			if (mdmon_running(st->container_devnm) &&
 					st->update_tail == NULL)
 				st->update_tail = &st->updates;
 		}
@@ -1930,7 +1917,7 @@ size_change_error:
 
 	memset(&info, 0, sizeof(info));
 	info.array = array;
-	sysfs_init(&info, fd, NoMdDev);
+	sysfs_init(&info, fd, NULL);
 	strcpy(info.text_version, sra->text_version);
 	info.component_size = s->size*2;
 	info.new_level = s->level;
@@ -2193,7 +2180,7 @@ static int raid10_reshape(char *container, int fd, char *devname,
 	int dir = 0;
 	int err = 0;
 
-	sra = sysfs_read(fd, 0,
+	sra = sysfs_read(fd, NULL,
 			 GET_COMPONENT|GET_DEVS|GET_OFFSET|GET_STATE|GET_CHUNK
 		);
 	if (!sra) {
@@ -2389,7 +2376,7 @@ static void get_space_after(int fd, struct supertype *st, struct mdinfo *info)
 	unsigned long long min_space_before = 0, min_space_after = 0;
 	int first = 1;
 
-	sra = sysfs_read(fd, 0, GET_DEVS);
+	sra = sysfs_read(fd, NULL, GET_DEVS);
 	if (!sra)
 		return;
 	for (sd = sra->devs; sd; sd = sd->next) {
@@ -2586,13 +2573,13 @@ static int reshape_array(char *container, int fd, char *devname,
 
 		if (reshape.level > 0 && st->ss->external) {
 			/* make sure mdmon is aware of the new level */
-			if (mdmon_running(st->container_dev))
+			if (mdmon_running(container))
 				flush_mdmon(container);
 
-			if (!mdmon_running(st->container_dev))
-				start_mdmon(st->container_dev);
+			if (!mdmon_running(container))
+				start_mdmon(container);
 			ping_monitor(container);
-			if (mdmon_running(st->container_dev) &&
+			if (mdmon_running(container) &&
 			    st->update_tail == NULL)
 				st->update_tail = &st->updates;
 		}
@@ -2609,7 +2596,7 @@ static int reshape_array(char *container, int fd, char *devname,
 		struct mdinfo *d;
 
 		if (info2) {
-			sysfs_init(info2, fd, st->devnum);
+			sysfs_init(info2, fd, st->devnm);
 			/* When increasing number of devices, we need to set
 			 * new raid_disks before adding these, or they might
 			 * be rejected.
@@ -2744,7 +2731,7 @@ started:
 				      &reshape, data_offset,
 				      force, verbose);
 	}
-	sra = sysfs_read(fd, 0,
+	sra = sysfs_read(fd, NULL,
 			 GET_COMPONENT|GET_DEVS|GET_OFFSET|GET_STATE|GET_CHUNK|
 			 GET_CACHE);
 	if (!sra) {
@@ -2958,7 +2945,7 @@ started:
 		delayed = 0;
 		mds = mdstat_read(0, 0);
 		for (m = mds; m; m = m->next)
-			if (m->devnum == devname2devnum(sra->sys_name)) {
+			if (strcmp(m->devnm, sra->sys_name) == 0) {
 				if (m->resync &&
 				    m->percent == RESYNC_DELAYED)
 					delayed = 1;
@@ -3025,7 +3012,7 @@ started:
 
 	if (st->ss->external) {
 		/* Re-load the metadata as much could have changed */
-		int cfd = open_dev(st->container_dev);
+		int cfd = open_dev(st->container_devnm);
 		if (cfd >= 0) {
 			flush_mdmon(container);
 			st->ss->free_super(st);
@@ -3087,7 +3074,7 @@ int reshape_container(char *container, char *devname,
 {
 	struct mdinfo *cc = NULL;
 	int rv = restart;
-	int last_devnum = -1;
+	char last_devnm[32] = "";
 
 	/* component_size is not meaningful for a container,
 	 * so pass '0' meaning 'no change'
@@ -3144,6 +3131,7 @@ int reshape_container(char *container, char *devname,
 		int fd;
 		struct mdstat_ent *mdstat;
 		char *adev;
+		int devid;
 
 		sysfs_free(cc);
 
@@ -3155,13 +3143,12 @@ int reshape_container(char *container, char *devname,
 				continue;
 
 			subarray = strchr(content->text_version+1, '/')+1;
-			mdstat = mdstat_by_subdev(subarray,
-						  devname2devnum(container));
+			mdstat = mdstat_by_subdev(subarray, container);
 			if (!mdstat)
 				continue;
 			if (mdstat->active == 0) {
-				pr_err("Skipping inactive "
-					"array md%i.\n", mdstat->devnum);
+				pr_err("Skipping inactive array %s.\n",
+				       mdstat->devnm);
 				free_mdstat(mdstat);
 				mdstat = NULL;
 				continue;
@@ -3171,20 +3158,19 @@ int reshape_container(char *container, char *devname,
 		if (!content)
 			break;
 
-		adev = map_dev(dev2major(mdstat->devnum),
-			       dev2minor(mdstat->devnum),
-			       0);
+		devid = devnm2devid(mdstat->devnm);
+		adev = map_dev(major(devid), minor(devid), 0);
 		if (!adev)
 			adev = content->text_version;
 
-		fd = open_dev(mdstat->devnum);
+		fd = open_dev(mdstat->devnm);
 		if (fd < 0) {
 			printf(Name ": Device %s cannot be opened for reshape.",
 			       adev);
 			break;
 		}
 
-		if (last_devnum == mdstat->devnum) {
+		if (strcmp(last_devnm, mdstat->devnm) == 0) {
 			/* Do not allow for multiple reshape_array() calls for
 			 * the same array.
 			 * It can happen when reshape_array() returns without
@@ -3200,11 +3186,11 @@ int reshape_container(char *container, char *devname,
 			close(fd);
 			break;
 		}
-		last_devnum = mdstat->devnum;
+		strcpy(last_devnm, mdstat->devnm);
 
-		sysfs_init(content, fd, mdstat->devnum);
+		sysfs_init(content, fd, mdstat->devnm);
 
-		if (mdmon_running(devname2devnum(container)))
+		if (mdmon_running(container))
 			flush_mdmon(container);
 
 		rv = reshape_array(container, fd, adev, st,
@@ -3222,7 +3208,7 @@ int reshape_container(char *container, char *devname,
 		if (rv)
 			break;
 
-		if (mdmon_running(devname2devnum(container)))
+		if (mdmon_running(container))
 			flush_mdmon(container);
 	}
 	if (!rv)
@@ -4368,7 +4354,6 @@ int Grow_continue_command(char *devname, int fd,
 	char *subarray = NULL;
 	struct mdinfo *cc = NULL;
 	struct mdstat_ent *mdstat = NULL;
-	char buf[40];
 	int cfd = -1;
 	int fd2 = -1;
 
@@ -4427,17 +4412,17 @@ int Grow_continue_command(char *devname, int fd,
 		}
 		st->ss->getinfo_super(st, content, NULL);
 	} else {
-		int container_dev;
+		char *container;
 
 		if (subarray) {
 			dprintf("subarray (%s)\n", subarray);
-			container_dev = st->container_dev;
-			cfd = open_dev_excl(st->container_dev);
+			container = st->container_devnm;
+			cfd = open_dev_excl(st->container_devnm);
 		} else {
-			container_dev = st->devnum;
+			container = st->devnm;
 			close(fd);
-			cfd = open_dev_excl(st->devnum);
-			dprintf("container (%i)\n", container_dev);
+			cfd = open_dev_excl(st->devnm);
+			dprintf("container (%s)\n", container);
 			fd = cfd;
 		}
 		if (cfd < 0) {
@@ -4446,7 +4431,6 @@ int Grow_continue_command(char *devname, int fd,
 			ret_val = 1;
 			goto Grow_continue_command_exit;
 		}
-		fmt_devname(buf, container_dev);
 
 		/* find in container array under reshape
 		 */
@@ -4482,18 +4466,18 @@ int Grow_continue_command(char *devname, int fd,
 				pr_err("cannot continue reshape of an array"
 				       " in container with unsupported"
 				       " metadata: %s(%s)\n",
-				       devname, buf);
+				       devname, container);
 				ret_val = 1;
 				goto Grow_continue_command_exit;
 			}
 
 			array = strchr(content->text_version+1, '/')+1;
-			mdstat = mdstat_by_subdev(array, container_dev);
+			mdstat = mdstat_by_subdev(array, container);
 			if (!mdstat)
 				continue;
 			if (mdstat->active == 0) {
-				pr_err("Skipping inactive "
-					"array md%i.\n", mdstat->devnum);
+				pr_err("Skipping inactive array %s.\n",
+				       mdstat->devnm);
 				free_mdstat(mdstat);
 				mdstat = NULL;
 				continue;
@@ -4506,23 +4490,22 @@ int Grow_continue_command(char *devname, int fd,
 			ret_val = 1;
 			goto Grow_continue_command_exit;
 		}
-		fd2 = open_dev(mdstat->devnum);
+		fd2 = open_dev(mdstat->devnm);
 		if (fd2 < 0) {
-			pr_err("cannot open (md%i)\n",
-				mdstat->devnum);
+			pr_err("cannot open (%s)\n", mdstat->devnm);
 			ret_val = 1;
 			goto Grow_continue_command_exit;
 		}
 
-		sysfs_init(content, fd2, mdstat->devnum);
+		sysfs_init(content, fd2, mdstat->devnm);
 
 		/* start mdmon in case it is not running
 		 */
-		if (!mdmon_running(container_dev))
-			start_mdmon(container_dev);
-		ping_monitor(buf);
+		if (!mdmon_running(container))
+			start_mdmon(container);
+		ping_monitor(container);
 
-		if (mdmon_running(container_dev))
+		if (mdmon_running(container))
 			st->update_tail = &st->updates;
 		else {
 			pr_err("No mdmon found. "
@@ -4566,16 +4549,14 @@ int Grow_continue(int mdfd, struct supertype *st, struct mdinfo *info,
 		return ret_val;
 
 	if (st->ss->external) {
-		char container[40];
-		int cfd = open_dev(st->container_dev);
+		int cfd = open_dev(st->container_devnm);
 
 		if (cfd < 0)
 			return 1;
 
-		fmt_devname(container, st->container_dev);
-		st->ss->load_container(st, cfd, container);
+		st->ss->load_container(st, cfd, st->container_devnm);
 		close(cfd);
-		ret_val = reshape_container(container, NULL, mdfd,
+		ret_val = reshape_container(st->container_devnm, NULL, mdfd,
 					    st, info, 0, backup_file,
 					    0, 1, freeze_reshape);
 	} else
diff --git a/Incremental.c b/Incremental.c
index 19e4a1ec..36f79ef5 100644
--- a/Incremental.c
+++ b/Incremental.c
@@ -291,7 +291,7 @@ int Incremental(char *devname, struct context *c,
 
 	mp = map_by_uuid(&map, info.uuid);
 	if (mp)
-		mdfd = open_dev(mp->devnum);
+		mdfd = open_dev(mp->devnm);
 	else
 		mdfd = -1;
 
@@ -304,7 +304,7 @@ int Incremental(char *devname, struct context *c,
 		if (mdfd < 0)
 			goto out_unlock;
 
-		sysfs_init(&info, mdfd, 0);
+		sysfs_init(&info, mdfd, NULL);
 
 		if (set_array_info(mdfd, st, &info) != 0) {
 			pr_err("failed to set array info for %s: %s\n",
@@ -323,8 +323,8 @@ int Incremental(char *devname, struct context *c,
 			rv = 2;
 			goto out_unlock;
 		}
-		sra = sysfs_read(mdfd, -1, (GET_DEVS | GET_STATE |
-					    GET_OFFSET | GET_SIZE));
+		sra = sysfs_read(mdfd, NULL, (GET_DEVS | GET_STATE |
+					      GET_OFFSET | GET_SIZE));
 
 		if (!sra || !sra->devs || sra->devs->disk.raid_disk >= 0) {
 			/* It really should be 'none' - must be old buggy
@@ -339,7 +339,7 @@ int Incremental(char *devname, struct context *c,
 		}
 		info.array.working_disks = 1;
 		/* 6/ Make sure /var/run/mdadm.map contains this array. */
-		map_update(&map, fd2devnum(mdfd),
+		map_update(&map, fd2devnm(mdfd),
 			   info.text_version,
 			   info.uuid, chosen_name);
 	} else {
@@ -353,13 +353,13 @@ int Incremental(char *devname, struct context *c,
 		struct supertype *st2;
 		struct mdinfo info2, *d;
 
-		sra = sysfs_read(mdfd, -1, (GET_DEVS | GET_STATE |
+		sra = sysfs_read(mdfd, NULL, (GET_DEVS | GET_STATE |
 					    GET_OFFSET | GET_SIZE));
 
 		if (mp->path)
 			strcpy(chosen_name, mp->path);
 		else
-			strcpy(chosen_name, devnum2devname(mp->devnum));
+			strcpy(chosen_name, mp->devnm);
 
 		/* It is generally not OK to add non-spare drives to a
 		 * running array as they are probably missing because
@@ -460,7 +460,7 @@ int Incremental(char *devname, struct context *c,
 	/* 7/ Is there enough devices to possibly start the array? */
 	/* 7a/ if not, finish with success. */
 	if (info.array.level == LEVEL_CONTAINER) {
-		int devnum = devnum; /* defined and used iff ->external */
+		char devnm[32];
 		/* Try to assemble within the container */
 		sysfs_uevent(sra, "change");
 		if (c->verbose >= 0)
@@ -469,7 +469,7 @@ int Incremental(char *devname, struct context *c,
 			       info.array.working_disks == 1?"":"s");
 		wait_for(chosen_name, mdfd);
 		if (st->ss->external)
-			devnum = fd2devnum(mdfd);
+			strcpy(devnm, fd2devnm(mdfd));
 		if (st->ss->load_container)
 			rv = st->ss->load_container(st, mdfd, NULL);
 		close(mdfd);
@@ -485,7 +485,7 @@ int Incremental(char *devname, struct context *c,
 		/* after spare is added, ping monitor for external metadata
 		 * so that it can eg. try to rebuild degraded array */
 		if (st->ss->external)
-			ping_monitor_by_id(devnum);
+			ping_monitor(devnm);
 		return rv;
 	}
 
@@ -494,7 +494,7 @@ int Incremental(char *devname, struct context *c,
 	 * things change.
 	 */
 	sysfs_free(sra);
-	sra = sysfs_read(mdfd, -1, (GET_DEVS | GET_STATE |
+	sra = sysfs_read(mdfd, NULL, (GET_DEVS | GET_STATE |
 				    GET_OFFSET | GET_SIZE));
 	active_disks = count_active(st, sra, mdfd, &avail, &info);
 	if (enough(info.array.level, info.array.raid_disks,
@@ -771,10 +771,9 @@ static int container_members_max_degradation(struct map_ent *map, struct map_ent
 	int max_degraded = 0;
 
 	for(; map; map = map->next) {
-		if (!is_subarray(map->metadata) ||
-		    devname2devnum(map->metadata+1) != me->devnum)
+		if (!metadata_container_matches(map->metadata, me->devnm))
 			continue;
-		afd = open_dev(map->devnum);
+		afd = open_dev(map->devnm);
 		if (afd < 0)
 			continue;
 		/* most accurate information regarding array degradation */
@@ -848,12 +847,12 @@ static int array_try_spare(char *devname, int *dfdp, struct dev_policy *pol,
 			}
 			free(st2);
 		}
-		sra = sysfs_read(-1, mp->devnum,
+		sra = sysfs_read(-1, mp->devnm,
 				 GET_DEVS|GET_OFFSET|GET_SIZE|GET_STATE|
 				 GET_DEGRADED|GET_COMPONENT|GET_VERSION);
 		if (!sra) {
 			/* Probably a container - no degraded info */
-			sra = sysfs_read(-1, mp->devnum,
+			sra = sysfs_read(-1, mp->devnm,
 					 GET_DEVS|GET_OFFSET|GET_SIZE|GET_STATE|
 					 GET_COMPONENT|GET_VERSION);
 			if (sra)
@@ -894,7 +893,7 @@ static int array_try_spare(char *devname, int *dfdp, struct dev_policy *pol,
 			/* true for containers, here we must read superblock
 			 * to obtain minimum spare size */
 			struct supertype *st3 = dup_super(st2);
-			int mdfd = open_dev(mp->devnum);
+			int mdfd = open_dev(mp->devnm);
 			if (mdfd < 0) {
 				free(st3);
 				goto next;
@@ -977,7 +976,7 @@ static int array_try_spare(char *devname, int *dfdp, struct dev_policy *pol,
 	}
 	if (chosen) {
 		/* add current device to chosen array as a spare */
-		int mdfd = open_dev(devname2devnum(chosen->sys_name));
+		int mdfd = open_dev(chosen->sys_name);
 		if (mdfd >= 0) {
 			struct mddev_dev devlist;
 			char devname[20];
@@ -1289,7 +1288,7 @@ int IncrementalScan(int verbose)
 		mdu_array_info_t array;
 		mdu_bitmap_file_t bmf;
 		struct mdinfo *sra;
-		int mdfd = open_dev(me->devnum);
+		int mdfd = open_dev(me->devnm);
 
 		if (mdfd < 0)
 			continue;
@@ -1329,16 +1328,16 @@ int IncrementalScan(int verbose)
 		/* FIXME check for reshape_active and consider not
 		 * starting array.
 		 */
-		sra = sysfs_read(mdfd, 0, 0);
+		sra = sysfs_read(mdfd, NULL, 0);
 		if (sra) {
 			if (sysfs_set_str(sra, NULL,
 					  "array_state", "read-auto") == 0) {
 				if (verbose >= 0)
 					pr_err("started array %s\n",
-					       me->path ?: devnum2devname(me->devnum));
+					       me->path ?: me->devnm);
 			} else {
 				pr_err("failed to start array %s: %s\n",
-				       me->path ?: devnum2devname(me->devnum),
+				       me->path ?: me->devnm,
 				       strerror(errno));
 				rv = 1;
 			}
@@ -1355,7 +1354,7 @@ static char *container2devname(char *devname)
 	if (devname[0] == '/') {
 		int fd = open(devname, O_RDONLY);
 		if (fd >= 0) {
-			mdname = devnum2devname(fd2devnum(fd));
+			mdname = xstrdup(fd2devnm(fd));
 			close(fd);
 		}
 	} else {
@@ -1366,7 +1365,7 @@ static char *container2devname(char *devname)
 			return mdname;
 		mp = map_by_uuid(&map, uuid);
 		if (mp)
-			mdname = devnum2devname(mp->devnum);
+			mdname = xstrdup(mp->devnm);
 		map_free(map);
 	}
 
@@ -1440,11 +1439,11 @@ static int Incremental_container(struct supertype *st, char *devname,
 		mp = map_by_uuid(&map, ra->uuid);
 
 		if (mp) {
-			mdfd = open_dev(mp->devnum);
+			mdfd = open_dev(mp->devnm);
 			if (mp->path)
 				strcpy(chosen_name, mp->path);
 			else
-				strcpy(chosen_name, devnum2devname(mp->devnum));
+				strcpy(chosen_name, mp->devnm);
 		} else {
 
 			/* Check in mdadm.conf for container == devname and
@@ -1599,7 +1598,7 @@ int IncrementalRemove(char *devname, char *id_path, int verbose)
 			"of any array\n", devname);
 		return 1;
 	}
-	mdfd = open_dev(ent->devnum);
+	mdfd = open_dev(ent->devnm);
 	if (mdfd < 0) {
 		pr_err("Cannot open array %s!!\n", ent->dev);
 		free_mdstat(ent);
@@ -1608,7 +1607,7 @@ int IncrementalRemove(char *devname, char *id_path, int verbose)
 
 	if (id_path) {
 		struct map_ent *map = NULL, *me;
-		me = map_by_devnum(&map, ent->devnum);
+		me = map_by_devnm(&map, ent->devnm);
 		if (me)
 			policy_save_path(id_path, me);
 		map_free(map);
@@ -1624,7 +1623,7 @@ int IncrementalRemove(char *devname, char *id_path, int verbose)
 		struct mdstat_ent *memb;
 		for (memb = mdstat ; memb ; memb = memb->next)
 			if (is_container_member(memb, ent->dev)) {
-				int subfd = open_dev(memb->devnum);
+				int subfd = open_dev(memb->devnm);
 				if (subfd >= 0) {
 					Manage_subdevs(memb->dev, subfd,
 						       &devlist, verbose, 0,
diff --git a/Kill.c b/Kill.c
index cc2e5893..f2fdb856 100644
--- a/Kill.c
+++ b/Kill.c
@@ -107,14 +107,14 @@ int Kill_subarray(char *dev, char *subarray, int verbose)
 		goto free_super;
 	}
 
-	if (is_subarray_active(subarray, st->devname)) {
+	if (is_subarray_active(subarray, st->devnm)) {
 		if (verbose >= 0)
 			pr_err("Subarray-%s still active, aborting\n",
 			       subarray);
 		goto free_super;
 	}
 
-	if (mdmon_running(st->devnum))
+	if (mdmon_running(st->devnm))
 		st->update_tail = &st->updates;
 
 	/* ok we've found our victim, drop the axe */
diff --git a/Manage.c b/Manage.c
index 4d9c0d2f..6267c0ca 100644
--- a/Manage.c
+++ b/Manage.c
@@ -54,7 +54,7 @@ int Manage_ro(char *devname, int fd, int readonly)
 	/* If this is an externally-managed array, we need to modify the
 	 * metadata_version so that mdmon doesn't undo our change.
 	 */
-	mdi = sysfs_read(fd, -1, GET_LEVEL|GET_VERSION);
+	mdi = sysfs_read(fd, NULL, GET_LEVEL|GET_VERSION);
 	if (mdi &&
 	    mdi->array.major_version == -1 &&
 	    is_subarray(mdi->text_version)) {
@@ -127,12 +127,12 @@ out:
 
 #ifndef MDASSEMBLE
 
-static void remove_devices(int devnum, char *path)
+static void remove_devices(char *devnm, char *path)
 {
 	/*
 	 * Remove names at 'path' - possibly with
 	 * partition suffixes - which link to the 'standard'
-	 * name for devnum.  These were probably created
+	 * name for devnm.  These were probably created
 	 * by mdadm when the array was assembled.
 	 */
 	char base[40];
@@ -146,10 +146,7 @@ static void remove_devices(int devnum, char *path)
 	if (!path)
 		return;
 
-	if (devnum >= 0)
-		sprintf(base, "/dev/md%d", devnum);
-	else
-		sprintf(base, "/dev/md_d%d", -1-devnum);
+	sprintf(base, "/dev/%s", devnm);
 	be = base + strlen(base);
 
 	path2 = xmalloc(strlen(path)+20);
@@ -214,19 +211,19 @@ int Manage_runstop(char *devname, int fd, int runstop,
 		struct map_ent *map = NULL;
 		struct stat stb;
 		struct mdinfo *mdi;
-		int devnum;
+		char devnm[32];
 		int err;
 		int count;
 		/* If this is an mdmon managed array, just write 'inactive'
 		 * to the array state and let mdmon clear up.
 		 */
-		devnum = fd2devnum(fd);
+		strcpy(devnm, fd2devnm(fd));
 		/* Get EXCL access first.  If this fails, then attempting
 		 * to stop is probably a bad idea.
 		 */
 		close(fd);
 		fd = open(devname, O_RDONLY|O_EXCL);
-		if (fd < 0 || fd2devnum(fd) != devnum) {
+		if (fd < 0 || strcmp(fd2devnm(fd), devnm) != 0) {
 			if (fd >= 0)
 				close(fd);
 			if (verbose >= 0)
@@ -237,7 +234,7 @@ int Manage_runstop(char *devname, int fd, int runstop,
 				       devname);
 			return 1;
 		}
-		mdi = sysfs_read(fd, -1, GET_LEVEL|GET_VERSION);
+		mdi = sysfs_read(fd, NULL, GET_LEVEL|GET_VERSION);
 		if (mdi &&
 		    mdi->array.level > 0 &&
 		    is_subarray(mdi->text_version)) {
@@ -269,7 +266,7 @@ int Manage_runstop(char *devname, int fd, int runstop,
 			/* Give monitor a chance to act */
 			ping_monitor(mdi->text_version);
 
-			fd = open_dev_excl(devnum);
+			fd = open_dev_excl(devnm);
 			if (fd < 0) {
 				if (verbose >= 0)
 					pr_err("failed to completely stop %s"
@@ -296,8 +293,8 @@ int Manage_runstop(char *devname, int fd, int runstop,
 			for (m = mds; m; m = m->next)
 				if (m->metadata_version &&
 				    strncmp(m->metadata_version, "external:", 9)==0 &&
-				    is_subarray(m->metadata_version+9) &&
-				    devname2devnum(m->metadata_version+10) == devnum) {
+				    metadata_container_matches(m->metadata_version+9,
+							       devnm)) {
 					if (verbose >= 0)
 						pr_err("Cannot stop container %s: "
 						       "member %s still active\n",
@@ -340,17 +337,17 @@ int Manage_runstop(char *devname, int fd, int runstop,
 		if (mdi)
 			sysfs_uevent(mdi, "change");
 
-		if (devnum != NoMdDev &&
+		if (devnm[0] &&
 		    (stat("/dev/.udev", &stb) != 0 ||
 		     check_env("MDADM_NO_UDEV"))) {
-			struct map_ent *mp = map_by_devnum(&map, devnum);
-			remove_devices(devnum, mp ? mp->path : NULL);
+			struct map_ent *mp = map_by_devnm(&map, devnm);
+			remove_devices(devnm, mp ? mp->path : NULL);
 		}
 
 		if (verbose >= 0)
 			pr_err("stopped %s\n", devname);
 		map_lock(&map);
-		map_remove(&map, devnum);
+		map_remove(&map, devnm);
 		map_unlock(&map);
 	out:
 		if (mdi)
@@ -774,10 +771,12 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
 		struct mdinfo new_mdi;
 		struct mdinfo *sra;
 		int container_fd;
-		int devnum = fd2devnum(fd);
+		char devnm[32];
 		int dfd;
 
-		container_fd = open_dev_excl(devnum);
+		strcpy(devnm, fd2devnm(fd));
+
+		container_fd = open_dev_excl(devnm);
 		if (container_fd < 0) {
 			pr_err("add failed for %s:"
 			       " could not get exclusive access to container\n",
@@ -788,7 +787,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
 
 		Kill(dv->devname, NULL, 0, -1, 0);
 		dfd = dev_open(dv->devname, O_RDWR | O_EXCL|O_DIRECT);
-		if (mdmon_running(tst->container_dev))
+		if (mdmon_running(tst->container_devnm))
 			tst->update_tail = &tst->updates;
 		if (tst->ss->add_to_super(tst, &disc, dfd,
 					  dv->devname, INVALID_SECTORS)) {
@@ -801,7 +800,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
 		else
 			tst->ss->sync_metadata(tst);
 
-		sra = sysfs_read(container_fd, -1, 0);
+		sra = sysfs_read(container_fd, NULL, 0);
 		if (!sra) {
 			pr_err("add failed for %s: sysfs_read failed\n",
 			       dv->devname);
@@ -825,7 +824,7 @@ int Manage_add(int fd, int tfd, struct mddev_dev *dv,
 			sysfs_free(sra);
 			return -1;
 		}
-		ping_monitor_by_id(devnum);
+		ping_monitor(devnm);
 		sysfs_free(sra);
 		close(container_fd);
 	} else {
@@ -858,8 +857,9 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
 		 * get an O_EXCL open on the container
 		 */
 		int ret;
-		int dnum = fd2devnum(fd);
-		lfd = open_dev_excl(dnum);
+		char devnm[32];
+		strcpy(devnm, fd2devnm(fd));
+		lfd = open_dev_excl(devnm);
 		if (lfd < 0) {
 			pr_err("Cannot get exclusive access "
 			       " to container - odd\n");
@@ -875,7 +875,7 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
 		if (rdev == 0)
 			ret = -1;
 		else
-			ret = sysfs_unique_holder(dnum, rdev);
+			ret = sysfs_unique_holder(devnm, rdev);
 		if (ret == 0) {
 			pr_err("%s is not a member, cannot remove.\n",
 			       dv->devname);
@@ -904,7 +904,7 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
 		if (err && errno == ENODEV) {
 			/* Old kernels rejected this if no personality
 			 * is registered */
-			struct mdinfo *sra = sysfs_read(fd, 0, GET_DEVS);
+			struct mdinfo *sra = sysfs_read(fd, NULL, GET_DEVS);
 			struct mdinfo *dv = NULL;
 			if (sra)
 				dv = sra->devs;
@@ -936,15 +936,14 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
 		 * 'add' event before reconciling this 'remove'
 		 * event.
 		 */
-		char *name = devnum2devname(fd2devnum(fd));
+		char *devnm = fd2devnm(fd);
 
-		if (!name) {
+		if (!devnm) {
 			pr_err("unable to get container name\n");
 			return -1;
 		}
 
-		ping_manager(name);
-		free(name);
+		ping_manager(devnm);
 	}
 	if (lfd >= 0)
 		close(lfd);
@@ -965,7 +964,7 @@ int Manage_replace(struct supertype *tst, int fd, struct mddev_dev *dv,
 	/* Need to find the device in sysfs and add 'want_replacement' to the
 	 * status.
 	 */
-	mdi = sysfs_read(fd, -1, GET_DEVS);
+	mdi = sysfs_read(fd, NULL, GET_DEVS);
 	if (!mdi || !mdi->devs) {
 		pr_err("Cannot find status of %s to enable replacement - strange\n",
 		       devname);
@@ -1016,7 +1015,7 @@ int Manage_with(struct supertype *tst, int fd, struct mddev_dev *dv,
 {
 	struct mdinfo *mdi, *di;
 	/* try to set 'slot' for 'rdev' in 'fd' to 'dv->used' */
-	mdi = sysfs_read(fd, -1, GET_DEVS|GET_STATE);
+	mdi = sysfs_read(fd, NULL, GET_DEVS|GET_STATE);
 	if (!mdi || !mdi->devs) {
 		pr_err("Cannot find status of %s to enable replacement - strange\n",
 		       devname);
@@ -1107,7 +1106,7 @@ int Manage_subdevs(char *devname, int fd,
 			devname);
 		goto abort;
 	}
-	sysfs_init(&info, fd, 0);
+	sysfs_init(&info, fd, NULL);
 
 	/* array.size is only 32 bits and may be truncated.
 	 * So read from sysfs if possible, and record number of sectors
@@ -1187,7 +1186,7 @@ int Manage_subdevs(char *devname, int fd,
 			}
 
 			sprintf(dname, "dev-%s", dv->devname);
-			sysfd = sysfs_open(fd2devnum(fd), dname, "block/dev");
+			sysfd = sysfs_open(fd2devnm(fd), dname, "block/dev");
 			if (sysfd >= 0) {
 				char dn[20];
 				int mj,mn;
@@ -1200,7 +1199,7 @@ int Manage_subdevs(char *devname, int fd,
 				sysfd = -1;
 			}
 			if (!found) {
-				sysfd = sysfs_open(fd2devnum(fd), dname, "state");
+				sysfd = sysfs_open(fd2devnm(fd), dname, "state");
 				if (sysfd < 0) {
 					pr_err("%s does not appear "
 						"to be a component of %s\n",
@@ -1412,7 +1411,7 @@ int Update_subarray(char *dev, char *subarray, char *update, struct mddev_ident
 		goto free_super;
 	}
 
-	if (mdmon_running(st->devnum))
+	if (mdmon_running(st->devnm))
 		st->update_tail = &st->updates;
 
 	rv = st->ss->update_subarray(st, subarray, update, ident);
diff --git a/Monitor.c b/Monitor.c
index a5e7aaab..607d3ddd 100644
--- a/Monitor.c
+++ b/Monitor.c
@@ -32,7 +32,7 @@
 
 struct state {
 	char *devname;
-	int devnum;	/* to sync with mdstat info */
+	char devnm[32];	/* to sync with mdstat info */
 	long utime;
 	int err;
 	char *spare_group;
@@ -42,9 +42,9 @@ struct state {
 	int devstate[MAX_DISKS];
 	dev_t devid[MAX_DISKS];
 	int percent;
-	int parent_dev; /* For subarray, devnum of parent.
-			 * For others, NoMdDev
-			 */
+	char parent_devnm[32]; /* For subarray, devnm of parent.
+				* For others, ""
+				*/
 	struct supertype *metadata;
 	struct state *subarray;/* for a container it is a link to first subarray
 				* for a subarray it is a link to next subarray
@@ -177,7 +177,7 @@ int Monitor(struct mddev_dev *devlist,
 				       mdlist->devname);
 			}
 			st->next = statelist;
-			st->devnum = INT_MAX;
+			st->devnm[0] = 0;
 			st->percent = RESYNC_UNKNOWN;
 			st->from_config = 1;
 			st->expected_spares = mdlist->spare_disks;
@@ -192,7 +192,7 @@ int Monitor(struct mddev_dev *devlist,
 			struct state *st = xcalloc(1, sizeof *st);
 			st->devname = xstrdup(dv->devname);
 			st->next = statelist;
-			st->devnum = INT_MAX;
+			st->devnm[0] = 0;
 			st->percent = RESYNC_UNKNOWN;
 			st->expected_spares = -1;
 			if (mdlist) {
@@ -483,20 +483,12 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 		close(fd);
 		return 0;
 	}
-	if (st->devnum == INT_MAX) {
-		struct stat stb;
-		if (fstat(fd, &stb) == 0 &&
-		    (S_IFMT&stb.st_mode)==S_IFBLK) {
-			if (major(stb.st_rdev) == MD_MAJOR)
-				st->devnum = minor(stb.st_rdev);
-			else
-				st->devnum = -1- (minor(stb.st_rdev)>>6);
-		}
-	}
+	if (st->devnm[0] == 0)
+		strcpy(st->devnm, fd2devnm(fd));
 
 	for (mse2 = mdstat ; mse2 ; mse2=mse2->next)
-		if (mse2->devnum == st->devnum) {
-			mse2->devnum = INT_MAX; /* flag it as "used" */
+		if (strcmp(mse2->devnm, st->devnm) == 0) {
+			mse2->devnm[0] = 0; /* flag it as "used" */
 			mse = mse2;
 		}
 
@@ -566,7 +558,7 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 		 * we should report that.
 		 */
 		struct mdinfo *sra =
-			sysfs_read(-1, st->devnum, GET_MISMATCH);
+			sysfs_read(-1, st->devnm, GET_MISMATCH);
 		if (sra && sra->mismatch_cnt > 0) {
 			char cnt[80];
 			snprintf(cnt, sizeof(cnt),
@@ -598,13 +590,17 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 
 	if (mse->metadata_version &&
 	    strncmp(mse->metadata_version, "external:", 9) == 0 &&
-	    is_subarray(mse->metadata_version+9))
-		st->parent_dev =
-			devname2devnum(mse->metadata_version+10);
-	else
-		st->parent_dev = NoMdDev;
+	    is_subarray(mse->metadata_version+9)) {
+		char *sl;
+		strcpy(st->parent_devnm,
+		       mse->metadata_version+10);
+		sl = strchr(st->parent_devnm, '/');
+		if (sl)
+			*sl = 0;
+	} else
+		st->parent_devnm[0] = 0;
 	if (st->metadata == NULL &&
-	    st->parent_dev == NoMdDev)
+	    st->parent_devnm[0] == 0)
 		st->metadata = super_by_fd(fd, NULL);
 
 	close(fd);
@@ -664,7 +660,7 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist,
 	int new_found = 0;
 
 	for (mse=mdstat; mse; mse=mse->next)
-		if (mse->devnum != INT_MAX &&
+		if (mse->devnm[0] &&
 		    (!mse->level  || /* retrieve containers */
 		     (strcmp(mse->level, "raid0") != 0 &&
 		      strcmp(mse->level, "linear") != 0))
@@ -672,7 +668,7 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist,
 			struct state *st = xcalloc(1, sizeof *st);
 			mdu_array_info_t array;
 			int fd;
-			st->devname = xstrdup(get_md_name(mse->devnum));
+			st->devname = xstrdup(get_md_name(mse->devnm));
 			if ((fd = open(st->devname, O_RDONLY)) < 0 ||
 			    ioctl(fd, GET_ARRAY_INFO, &array)< 0) {
 				/* no such array */
@@ -689,16 +685,19 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist,
 			close(fd);
 			st->next = *statelist;
 			st->err = 1;
-			st->devnum = mse->devnum;
+			strcpy(st->devnm, mse->devnm);
 			st->percent = RESYNC_UNKNOWN;
 			st->expected_spares = -1;
 			if (mse->metadata_version &&
 			    strncmp(mse->metadata_version, "external:", 9) == 0 &&
-			    is_subarray(mse->metadata_version+9))
-				st->parent_dev =
-					devname2devnum(mse->metadata_version+10);
-			else
-				st->parent_dev = NoMdDev;
+			    is_subarray(mse->metadata_version+9)) {
+				char *sl;
+				strcpy(st->parent_devnm,
+					mse->metadata_version+10);
+				sl = strchr(st->parent_devnm, '/');
+				*sl = 0;
+			} else
+				st->parent_devnm[0] = 0;
 			*statelist = st;
 			if (test)
 				alert("TestMessage", st->devname, NULL, info);
@@ -779,7 +778,7 @@ static dev_t choose_spare(struct state *from, struct state *to,
 			    dev_size < min_size)
 				continue;
 
-			pol = devnum_policy(from->devid[d]);
+			pol = devid_policy(from->devid[d]);
 			if (from->spare_group)
 				pol_add(&pol, pol_domain,
 					from->spare_group, NULL);
@@ -871,7 +870,7 @@ static void try_spare_migration(struct state *statelist, struct alert_info *info
 			struct state *to = st;
 			unsigned long long min_size;
 
-			if (to->parent_dev != NoMdDev && !to->parent)
+			if (to->parent_devnm[0] && !to->parent)
 				/* subarray monitored without parent container
 				 * we can't move spares here */
 				continue;
@@ -939,11 +938,11 @@ static void link_containers_with_subarrays(struct state *list)
 		st->subarray = NULL;
 	}
 	for (st = list; st; st = st->next)
-		if (st->parent_dev != NoMdDev)
+		if (st->parent_devnm[0])
 			for (cont = list; cont; cont = cont->next)
 				if (!cont->err &&
-				    cont->parent_dev == NoMdDev &&
-				    cont->devnum == st->parent_dev) {
+				    cont->parent_devnm[0] == 0 &&
+				    strcmp(cont->devnm, st->parent_devnm) == 0) {
 					st->parent = cont;
 					st->subarray = cont->subarray;
 					cont->subarray = st;
@@ -955,7 +954,7 @@ static void link_containers_with_subarrays(struct state *list)
 int Wait(char *dev)
 {
 	struct stat stb;
-	int devnum;
+	char devnm[32];
 	int rv = 1;
 
 	if (stat(dev, &stb) != 0) {
@@ -963,14 +962,14 @@ int Wait(char *dev)
 			strerror(errno));
 		return 2;
 	}
-	devnum = stat2devnum(&stb);
+	strcpy(devnm, stat2devnm(&stb));
 
 	while(1) {
 		struct mdstat_ent *ms = mdstat_read(1, 0);
 		struct mdstat_ent *e;
 
 		for (e=ms ; e; e=e->next)
-			if (e->devnum == devnum)
+			if (strcmp(e->devnm, devnm) == 0)
 				break;
 
 		if (!e || e->percent == RESYNC_NONE) {
@@ -979,7 +978,7 @@ int Wait(char *dev)
 				if (is_subarray(&e->metadata_version[9]))
 					ping_monitor(&e->metadata_version[9]);
 				else
-					ping_monitor_by_id(devnum);
+					ping_monitor(devnm);
 			}
 			free_mdstat(ms);
 			return rv;
@@ -1000,7 +999,7 @@ int WaitClean(char *dev, int sock, int verbose)
 	int fd;
 	struct mdinfo *mdi;
 	int rv = 1;
-	int devnum;
+	char devnm[32];
 
 	fd = open(dev, O_RDONLY);
 	if (fd < 0) {
@@ -1009,8 +1008,8 @@ int WaitClean(char *dev, int sock, int verbose)
 		return 1;
 	}
 
-	devnum = fd2devnum(fd);
-	mdi = sysfs_read(fd, devnum, GET_VERSION|GET_LEVEL|GET_SAFEMODE);
+	strcpy(devnm, fd2devnm(fd));
+	mdi = sysfs_read(fd, devnm, GET_VERSION|GET_LEVEL|GET_SAFEMODE);
 	if (!mdi) {
 		if (verbose)
 			pr_err("Failed to read sysfs attributes for "
@@ -1038,7 +1037,7 @@ int WaitClean(char *dev, int sock, int verbose)
 		rv = 0;
 
 	if (rv) {
-		int state_fd = sysfs_open(fd2devnum(fd), NULL, "array_state");
+		int state_fd = sysfs_open(fd2devnm(fd), NULL, "array_state");
 		char buf[20];
 		fd_set fds;
 		struct timeval tm;
diff --git a/config.c b/config.c
index 8461309a..0eb2c8d1 100644
--- a/config.c
+++ b/config.c
@@ -995,7 +995,7 @@ int devname_matches(char *name, char *match)
 
 int conf_name_is_free(char *name)
 {
-	/* Check if this name is already take by an ARRAY entry in
+	/* Check if this name is already taken by an ARRAY entry in
 	 * the config file.
 	 * It can be taken either by a match on devname, name, or
 	 * even super-minor.
diff --git a/lib.c b/lib.c
index 8124fa1b..19580296 100644
--- a/lib.c
+++ b/lib.c
@@ -57,72 +57,59 @@ static int mdp_major = -1;
 	return mdp_major;
 }
 
-
-void fmt_devname(char *name, int num)
-{
-	if (num >= 0)
-		sprintf(name, "md%d", num);
-	else
-		sprintf(name, "md_d%d", -1-num);
-}
-
-char *devnum2devname(int num)
-{
-	char name[100];
-	fmt_devname(name,num);
-	return xstrdup(name);
-}
-
-int devname2devnum(char *name)
-{
-	char *ep;
-	int num;
-	if (strncmp(name, "md_d", 4)==0)
-		num = -1-strtoul(name+4, &ep, 10);
-	else
-		num = strtoul(name+2, &ep, 10);
-	return num;
-}
-
-int stat2devnum(struct stat *st)
+char *devid2devnm(int devid)
 {
 	char path[30];
 	char link[200];
-	char *cp;
+	static char devnm[32];
+	char *cp, *ep;
 	int n;
 
-	if ((S_IFMT & st->st_mode) == S_IFBLK) {
-		if (major(st->st_rdev) == MD_MAJOR)
-			return minor(st->st_rdev);
-		else if (major(st->st_rdev) == (unsigned)get_mdp_major())
-			return -1- (minor(st->st_rdev)>>MdpMinorShift);
-
-		/* must be an extended-minor partition. Look at the
-		 * /sys/dev/block/%d:%d link which must look like
-		 * ../../block/mdXXX/mdXXXpYY
-		 */
-		sprintf(path, "/sys/dev/block/%d:%d", major(st->st_rdev),
-			minor(st->st_rdev));
-		n = readlink(path, link, sizeof(link)-1);
-		if (n <= 0)
-			return NoMdDev;
+	/* Might be an extended-minor partition or a
+	 * named md device. Look at the
+	 * /sys/dev/block/%d:%d link which must look like
+	 *    ../../block/mdXXX/mdXXXpYY
+	 * or
+	 *    ...../block/md_FOO
+	 */
+	sprintf(path, "/sys/dev/block/%d:%d", major(devid),
+		minor(devid));
+	n = readlink(path, link, sizeof(link)-1);
+	if (n > 0) {
 		link[n] = 0;
-		cp = strrchr(link, '/');
-		if (cp) *cp = 0;
-		cp = strrchr(link, '/');
-		if (cp && strncmp(cp, "/md", 3) == 0)
-			return devname2devnum(cp+1);
+		cp = strstr(link, "/block/");
+		if (cp) {
+			cp += 7;
+			ep = strchr(cp, '/');
+			if (ep)
+				*ep = 0;
+			strcpy(devnm, cp);
+			return devnm;
+		}
 	}
-	return NoMdDev;
+	if (major(devid) == MD_MAJOR)
+		sprintf(devnm,"md%d", minor(devid));
+	else if (major(devid) == (unsigned)get_mdp_major())
+		sprintf(devnm,"md_d%d",
+			(minor(devid)>>MdpMinorShift));
+	else
+		return NULL;
+	return devnm;
+}
 
+char *stat2devnm(struct stat *st)
+{
+	if ((S_IFMT & st->st_mode) != S_IFBLK)
+		return NULL;
+	return devid2devnm(st->st_rdev);
 }
 
-int fd2devnum(int fd)
+char *fd2devnm(int fd)
 {
 	struct stat stb;
 	if (fstat(fd, &stb) == 0)
-		return stat2devnum(&stb);
-	return NoMdDev;
+		return stat2devnm(&stb);
+	return NULL;
 }
 
 
diff --git a/managemon.c b/managemon.c
index f0399b88..d155b042 100644
--- a/managemon.c
+++ b/managemon.c
@@ -134,7 +134,7 @@ static void free_aa(struct active_array *aa)
 	/* Note that this doesn't close fds if they are being used
 	 * by a clone.  ->container will be set for a clone
 	 */
-	dprintf("%s: devnum: %d\n", __func__, aa->devnum);
+	dprintf("%s: sys_name: %s\n", __func__, aa->info.sys_name);
 	if (!aa->container)
 		close_aa(aa);
 	while (aa->info.devs) {
@@ -359,7 +359,7 @@ static void manage_container(struct mdstat_ent *mdstat,
 		 * To see what is removed and what is added.
 		 * These need to be remove from, or added to, the array
 		 */
-		mdi = sysfs_read(-1, mdstat->devnum, GET_DEVS);
+		mdi = sysfs_read(-1, mdstat->devnm, GET_DEVS);
 		if (!mdi) {
 			/* invalidate the current count so we can try again */
 			container->devcnt = -1;
@@ -409,10 +409,10 @@ static int disk_init_and_add(struct mdinfo *disk, struct mdinfo *clone,
 		return -1;
 
 	*disk = *clone;
-	disk->recovery_fd = sysfs_open(aa->devnum, disk->sys_name, "recovery_start");
+	disk->recovery_fd = sysfs_open(aa->info.sys_name, disk->sys_name, "recovery_start");
 	if (disk->recovery_fd < 0)
 		return -1;
-	disk->state_fd = sysfs_open(aa->devnum, disk->sys_name, "state");
+	disk->state_fd = sysfs_open(aa->info.sys_name, disk->sys_name, "state");
 	if (disk->state_fd < 0) {
 		close(disk->recovery_fd);
 		return -1;
@@ -552,7 +552,7 @@ static void manage_member(struct mdstat_ent *mdstat,
 		unsigned long long array_size;
 		struct active_array *newa = NULL;
 		a->check_reshape = 0;
-		info = sysfs_read(-1, mdstat->devnum,
+		info = sysfs_read(-1, mdstat->devnm,
 				  GET_DEVS|GET_OFFSET|GET_SIZE|GET_STATE);
 		if (!info)
 			goto out2;
@@ -631,7 +631,7 @@ static void manage_new(struct mdstat_ent *mdstat,
 	    strcmp(mdstat->level, "linear") == 0)
 		return;
 
-	mdi = sysfs_read(-1, mdstat->devnum,
+	mdi = sysfs_read(-1, mdstat->devnm,
 			 GET_LEVEL|GET_CHUNK|GET_DISKS|GET_COMPONENT|
 			 GET_DEGRADED|GET_DEVS|GET_OFFSET|GET_SIZE|GET_STATE);
 
@@ -640,15 +640,14 @@ static void manage_new(struct mdstat_ent *mdstat,
 		return;
 	new = xcalloc(1, sizeof(*new));
 
-	new->devnum = mdstat->devnum;
-	strcpy(new->info.sys_name, devnum2devname(new->devnum));
+	strcpy(new->info.sys_name, mdstat->devnm);
 
 	new->prev_state = new->curr_state = new->next_state = inactive;
 	new->prev_action= new->curr_action= new->next_action= idle;
 
 	new->container = container;
 
-	inst = to_subarray(mdstat, container->devname);
+	inst = to_subarray(mdstat, container->devnm);
 
 	new->info.array = mdi->array;
 	new->info.component_size = mdi->component_size;
@@ -673,11 +672,11 @@ static void manage_new(struct mdstat_ent *mdstat,
 		}
 	}
 
-	new->action_fd = sysfs_open(new->devnum, NULL, "sync_action");
-	new->info.state_fd = sysfs_open(new->devnum, NULL, "array_state");
-	new->resync_start_fd = sysfs_open(new->devnum, NULL, "resync_start");
-	new->metadata_fd = sysfs_open(new->devnum, NULL, "metadata_version");
-	new->sync_completed_fd = sysfs_open(new->devnum, NULL, "sync_completed");
+	new->action_fd = sysfs_open(new->info.sys_name, NULL, "sync_action");
+	new->info.state_fd = sysfs_open(new->info.sys_name, NULL, "array_state");
+	new->resync_start_fd = sysfs_open(new->info.sys_name, NULL, "resync_start");
+	new->metadata_fd = sysfs_open(new->info.sys_name, NULL, "metadata_version");
+	new->sync_completed_fd = sysfs_open(new->info.sys_name, NULL, "sync_completed");
 	dprintf("%s: inst: %d action: %d state: %d\n", __func__, atoi(inst),
 		new->action_fd, new->info.state_fd);
 
@@ -732,16 +731,16 @@ void manage(struct mdstat_ent *mdstat, struct supertype *container)
 
 	for ( ; mdstat ; mdstat = mdstat->next) {
 		struct active_array *a;
-		if (mdstat->devnum == container->devnum) {
+		if (strcmp(mdstat->devnm, container->devnm) == 0) {
 			manage_container(mdstat, container);
 			continue;
 		}
-		if (!is_container_member(mdstat, container->devname))
+		if (!is_container_member(mdstat, container->devnm))
 			/* Not for this array */
 			continue;
 		/* Looks like a member of this container */
 		for (a = container->arrays; a; a = a->next) {
-			if (mdstat->devnum == a->devnum) {
+			if (strcmp(mdstat->devnm, a->info.sys_name) == 0) {
 				if (a->container && a->to_remove == 0)
 					manage_member(mdstat, a);
 				break;
diff --git a/mapfile.c b/mapfile.c
index 34ebdb54..149f67b2 100644
--- a/mapfile.c
+++ b/mapfile.c
@@ -88,10 +88,7 @@ int map_write(struct map_ent *mel)
 	for (; mel; mel = mel->next) {
 		if (mel->bad)
 			continue;
-		if (mel->devnum < 0)
-			fprintf(f, "mdp%d ", -1-mel->devnum);
-		else
-			fprintf(f, "md%d ", mel->devnum);
+		fprintf(f, "%s ", mel->devnm);
 		fprintf(f, "%s ", mel->metadata);
 		fprintf(f, "%08x:%08x:%08x:%08x ", mel->uuid[0],
 			mel->uuid[1], mel->uuid[2], mel->uuid[3]);
@@ -164,11 +161,11 @@ void map_fork(void)
 }
 
 void map_add(struct map_ent **melp,
-	    int devnum, char *metadata, int uuid[4], char *path)
+	     char * devnm, char *metadata, int uuid[4], char *path)
 {
 	struct map_ent *me = xmalloc(sizeof(*me));
 
-	me->devnum = devnum;
+	strcpy(me->devnm, devnm);
 	strcpy(me->metadata, metadata);
 	memcpy(me->uuid, uuid, 16);
 	me->path = path ? xstrdup(path) : NULL;
@@ -182,9 +179,9 @@ void map_read(struct map_ent **melp)
 	FILE *f;
 	char buf[8192];
 	char path[200];
-	int devnum, uuid[4];
+	int uuid[4];
+	char devnm[32];
 	char metadata[30];
-	char nam[4];
 
 	*melp = NULL;
 
@@ -198,14 +195,10 @@ void map_read(struct map_ent **melp)
 
 	while (fgets(buf, sizeof(buf), f)) {
 		path[0] = 0;
-		if (sscanf(buf, " %3[mdp]%d %s %x:%x:%x:%x %200s",
-			   nam, &devnum, metadata, uuid, uuid+1,
+		if (sscanf(buf, " %s %s %x:%x:%x:%x %200s",
+			   devnm, metadata, uuid, uuid+1,
 			   uuid+2, uuid+3, path) >= 7) {
-			if (strncmp(nam, "md", 2) != 0)
-				continue;
-			if (nam[2] == 'p')
-				devnum = -1 - devnum;
-			map_add(melp, devnum, metadata, uuid, path);
+			map_add(melp, devnm, metadata, uuid, path);
 		}
 	}
 	fclose(f);
@@ -221,7 +214,7 @@ void map_free(struct map_ent *map)
 	}
 }
 
-int map_update(struct map_ent **mpp, int devnum, char *metadata,
+int map_update(struct map_ent **mpp, char *devnm, char *metadata,
 	       int *uuid, char *path)
 {
 	struct map_ent *map, *mp;
@@ -233,7 +226,7 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
 		map_read(&map);
 
 	for (mp = map ; mp ; mp=mp->next)
-		if (mp->devnum == devnum) {
+		if (strcmp(mp->devnm, devnm) == 0) {
 			strcpy(mp->metadata, metadata);
 			memcpy(mp->uuid, uuid, 16);
 			free(mp->path);
@@ -242,7 +235,7 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
 			break;
 		}
 	if (!mp)
-		map_add(&map, devnum, metadata, uuid, path);
+		map_add(&map, devnm, metadata, uuid, path);
 	if (mpp)
 		*mpp = NULL;
 	rv = map_write(map);
@@ -250,7 +243,7 @@ int map_update(struct map_ent **mpp, int devnum, char *metadata,
 	return rv;
 }
 
-void map_delete(struct map_ent **mapp, int devnum)
+void map_delete(struct map_ent **mapp, char *devnm)
 {
 	struct map_ent *mp;
 
@@ -258,7 +251,7 @@ void map_delete(struct map_ent **mapp, int devnum)
 		map_read(mapp);
 
 	for (mp = *mapp; mp; mp = *mapp) {
-		if (mp->devnum == devnum) {
+		if (strcmp(mp->devnm, devnm) == 0) {
 			*mapp = mp->next;
 			free(mp->path);
 			free(mp);
@@ -267,12 +260,12 @@ void map_delete(struct map_ent **mapp, int devnum)
 	}
 }
 
-void map_remove(struct map_ent **mapp, int devnum)
+void map_remove(struct map_ent **mapp, char *devnm)
 {
-	if (devnum == NoMdDev)
+	if (devnm[0] == 0)
 		return;
 
-	map_delete(mapp, devnum);
+	map_delete(mapp, devnm);
 	map_write(*mapp);
 	map_free(*mapp);
 }
@@ -286,7 +279,7 @@ struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
 	for (mp = *map ; mp ; mp = mp->next) {
 		if (memcmp(uuid, mp->uuid, 16) != 0)
 			continue;
-		if (!mddev_busy(mp->devnum)) {
+		if (!mddev_busy(mp->devnm)) {
 			mp->bad = 1;
 			continue;
 		}
@@ -295,16 +288,16 @@ struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4])
 	return NULL;
 }
 
-struct map_ent *map_by_devnum(struct map_ent **map, int devnum)
+struct map_ent *map_by_devnm(struct map_ent **map, char *devnm)
 {
 	struct map_ent *mp;
 	if (!*map)
 		map_read(map);
 
 	for (mp = *map ; mp ; mp = mp->next) {
-		if (mp->devnum != devnum)
+		if (strcmp(mp->devnm, devnm) != 0)
 			continue;
-		if (!mddev_busy(mp->devnum)) {
+		if (!mddev_busy(mp->devnm)) {
 			mp->bad = 1;
 			continue;
 		}
@@ -326,7 +319,7 @@ struct map_ent *map_by_name(struct map_ent **map, char *name)
 			continue;
 		if (strcmp(mp->path+8, name) != 0)
 			continue;
-		if (!mddev_busy(mp->devnum)) {
+		if (!mddev_busy(mp->devnm)) {
 			mp->bad = 1;
 			continue;
 		}
@@ -360,7 +353,6 @@ void RebuildMap(void)
 	struct mdstat_ent *mdstat = mdstat_read(0, 0);
 	struct mdstat_ent *md;
 	struct map_ent *map = NULL;
-	int mdp = get_mdp_major();
 	int require_homehost;
 	char sys_hostname[256];
 	char *homehost = conf_get_homehost(&require_homehost);
@@ -373,7 +365,7 @@ void RebuildMap(void)
 	}
 
 	for (md = mdstat ; md ; md = md->next) {
-		struct mdinfo *sra = sysfs_read(-1, md->devnum, GET_DEVS);
+		struct mdinfo *sra = sysfs_read(-1, md->devnm, GET_DEVS);
 		struct mdinfo *sd;
 
 		if (!sra)
@@ -384,6 +376,7 @@ void RebuildMap(void)
 			char dn[30];
 			int dfd;
 			int ok;
+			int devid;
 			struct supertype *st;
 			char *subarray = NULL;
 			char *path;
@@ -412,10 +405,8 @@ void RebuildMap(void)
 			if (!info)
 				continue;
 
-			if (md->devnum >= 0)
-				path = map_dev(MD_MAJOR, md->devnum, 0);
-			else
-				path = map_dev(mdp, (-1-md->devnum)<< 6, 0);
+			devid = devnm2devid(md->devnm);
+			path = map_dev(major(devid), minor(devid), 0);
 			if (path == NULL ||
 			    strncmp(path, "/dev/md/", 8) != 0) {
 				/* We would really like a name that provides
@@ -489,7 +480,7 @@ void RebuildMap(void)
 					path = namebuf;
 				}
 			}
-			map_add(&map, md->devnum,
+			map_add(&map, md->devnm,
 				info->text_version,
 				info->uuid, path);
 			st->ss->free_super(st);
@@ -501,7 +492,7 @@ void RebuildMap(void)
 	/* 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,
+			struct mdinfo *sra = sysfs_read(-1, md->devnm,
 							GET_VERSION);
 			if (sra)
 				sysfs_uevent(sra, "change");
diff --git a/mdadm.c b/mdadm.c
index f22fd7ba..214afa31 100644
--- a/mdadm.c
+++ b/mdadm.c
@@ -1457,7 +1457,7 @@ int main(int argc, char *argv[])
 				rv = 1;
 				break;
 			}
-			sysfs_init(&sra, mdfd, 0);
+			sysfs_init(&sra, mdfd, NULL);
 			if (array_size == MAX_SIZE)
 				err = sysfs_set_str(&sra, NULL, "array_size", "default");
 			else
@@ -1658,12 +1658,12 @@ static int misc_scan(char devmode, struct context *c)
 					"external:/", 10) == 0;
 			if (members != member)
 				continue;
-			me = map_by_devnum(&map, e->devnum);
+			me = map_by_devnm(&map, e->devnm);
 			if (me && me->path
 			    && strcmp(me->path, "/unknown") != 0)
 				name = me->path;
 			else
-				name = get_md_name(e->devnum);
+				name = get_md_name(e->devnm);
 
 			if (!name) {
 				pr_err("cannot find device file for %s\n",
@@ -1697,7 +1697,7 @@ static int stop_scan(int verbose)
 		if (!progress) last = 1;
 		progress = 0; err = 0;
 		for (e=ms ; e ; e=e->next) {
-			char *name = get_md_name(e->devnum);
+			char *name = get_md_name(e->devnm);
 			int mdfd;
 
 			if (!name) {
diff --git a/mdadm.h b/mdadm.h
index 7ffac8f9..c7b5183b 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -448,7 +448,7 @@ typedef struct mapping {
 
 struct mdstat_ent {
 	char		*dev;
-	int		devnum;
+	char		devnm[32];
 	int		active;
 	char		*level;
 	char		*pattern; /* U or up, _ for down */
@@ -468,30 +468,30 @@ extern struct mdstat_ent *mdstat_read(int hold, int start);
 extern void free_mdstat(struct mdstat_ent *ms);
 extern void mdstat_wait(int seconds);
 extern void mdstat_wait_fd(int fd, const sigset_t *sigmask);
-extern int mddev_busy(int devnum);
+extern int mddev_busy(char *devnm);
 extern struct mdstat_ent *mdstat_by_component(char *name);
-extern struct mdstat_ent *mdstat_by_subdev(char *subdev, int container);
+extern struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container);
 
 struct map_ent {
 	struct map_ent *next;
-	int	devnum;
+	char	devnm[32];
 	char	metadata[20];
 	int	uuid[4];
 	int	bad;
 	char	*path;
 };
-extern int map_update(struct map_ent **mpp, int devnum, char *metadata,
+extern int map_update(struct map_ent **mpp, char *devnm, char *metadata,
 		      int uuid[4], char *path);
-extern void map_remove(struct map_ent **map, int devnum);
+extern void map_remove(struct map_ent **map, char *devnm);
 extern struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4]);
-extern struct map_ent *map_by_devnum(struct map_ent **map, int devnum);
+extern struct map_ent *map_by_devnm(struct map_ent **map, char *devnm);
 extern struct map_ent *map_by_name(struct map_ent **map, char *name);
 extern void map_read(struct map_ent **melp);
 extern int map_write(struct map_ent *mel);
-extern void map_delete(struct map_ent **mapp, int devnum);
+extern void map_delete(struct map_ent **mapp, char *devnm);
 extern void map_free(struct map_ent *map);
 extern void map_add(struct map_ent **melp,
-		    int devnum, char *metadata, int uuid[4], char *path);
+		    char *devnm, char *metadata, int uuid[4], char *path);
 extern int map_lock(struct map_ent **melp);
 extern void map_unlock(struct map_ent **melp);
 extern void map_fork(void);
@@ -518,12 +518,12 @@ enum sysfs_read_flags {
 };
 
 /* If fd >= 0, get the array it is open on,
- * else use devnum. >=0 -> major9. <0.....
+ * else use devnm.
  */
-extern int sysfs_open(int devnum, char *devname, char *attr);
-extern void sysfs_init(struct mdinfo *mdi, int fd, int devnum);
+extern int sysfs_open(char *devnm, char *devname, char *attr);
+extern void sysfs_init(struct mdinfo *mdi, int fd, char *devnm);
 extern void sysfs_free(struct mdinfo *sra);
-extern struct mdinfo *sysfs_read(int fd, int devnum, unsigned long options);
+extern struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options);
 extern int sysfs_attr_match(const char *attr, const char *str);
 extern int sysfs_match_word(const char *word, char **list);
 extern int sysfs_set_str(struct mdinfo *sra, struct mdinfo *dev,
@@ -547,7 +547,7 @@ extern int sysfs_set_safemode(struct mdinfo *sra, unsigned long ms);
 extern int sysfs_set_array(struct mdinfo *info, int vers);
 extern int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume);
 extern int sysfs_disk_to_scsi_id(int fd, __u32 *id);
-extern int sysfs_unique_holder(int devnum, long rdev);
+extern int sysfs_unique_holder(char *devnm, long rdev);
 extern int sysfs_freeze_array(struct mdinfo *sra);
 extern int load_sys(char *path, char *buf);
 extern int reshape_prepare_fdlist(char *devname,
@@ -925,7 +925,7 @@ struct supertype {
 	struct superswitch *ss;
 	int minor_version;
 	int max_devs;
-	int container_dev;    /* devnum of container */
+	char container_devnm[32];    /* devnm of container */
 	void *sb;
 	void *info;
 	int ignore_hw_compat; /* used to inform metadata handlers that it should ignore
@@ -939,10 +939,9 @@ struct supertype {
 	/* extra stuff used by mdmon */
 	struct active_array *arrays;
 	int sock; /* listen to external programs */
-	int devnum;
-	char *devname; /* e.g. md0.  This appears in metadata_verison:
-			*  external:/md0/12
-			*/
+	char devnm[32]; /* e.g. md0.  This appears in metadata_version:
+			 *  external:/md0/12
+			 */
 	int devcnt;
 	int retry_soon;
 
@@ -1017,7 +1016,7 @@ extern void policy_free(void);
 
 extern struct dev_policy *path_policy(char *path, char *type);
 extern struct dev_policy *disk_policy(struct mdinfo *disk);
-extern struct dev_policy *devnum_policy(int dev);
+extern struct dev_policy *devid_policy(int devid);
 extern void dev_policy_free(struct dev_policy *p);
 
 //extern void pol_new(struct dev_policy **pol, char *name, char *val, char *metadata);
@@ -1049,7 +1048,7 @@ extern int domain_test(struct domainlist *dom, struct dev_policy *pol,
 		       const char *metadata);
 extern struct domainlist *domain_from_array(struct mdinfo *mdi,
 					    const char *metadata);
-extern void domainlist_add_dev(struct domainlist **dom, int devnum,
+extern void domainlist_add_dev(struct domainlist **dom, int devid,
 			       const char *metadata);
 extern void domain_free(struct domainlist *dl);
 extern void domain_merge(struct domainlist **domp, struct dev_policy *pol,
@@ -1195,9 +1194,9 @@ extern int check_partitions(int fd, char *dname,
 
 extern int get_mdp_major(void);
 extern int dev_open(char *dev, int flags);
-extern int open_dev(int devnum);
-extern int open_dev_flags(int devnum, int flags);
-extern int open_dev_excl(int devnum);
+extern int open_dev(char *devnm);
+extern int open_dev_flags(char *devnm, int flags);
+extern int open_dev_excl(char *devnm);
 extern int is_standard(char *dev, int *nump);
 extern int same_dev(char *one, char *two);
 extern int compare_paths (char* path1,char* path2);
@@ -1271,11 +1270,12 @@ extern char *human_size(long long bytes);
 extern char *human_size_brief(long long bytes, int prefix);
 extern void print_r10_layout(int layout);
 
-#define NoMdDev (1<<23)
-extern int find_free_devnum(int use_partitions);
+extern char *find_free_devnm(int use_partitions);
 
 extern void put_md_name(char *name);
-extern char *get_md_name(int dev);
+extern char *devid2devnm(int devid);
+extern int devnm2devid(char *devnm);
+extern char *get_md_name(char *devnm);
 
 extern char DefaultConfFile[];
 
@@ -1288,16 +1288,18 @@ extern int create_mddev(char *dev, char *name, int autof, int trustworthy,
 #define	METADATA 3
 extern int open_mddev(char *dev, int report_errors);
 extern int open_container(int fd);
+extern int metadata_container_matches(char *metadata, char *devnm);
+extern int metadata_subdev_matches(char *metadata, char *devnm);
 extern int is_container_member(struct mdstat_ent *ent, char *devname);
 extern int is_subarray_active(char *subarray, char *devname);
 extern int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet);
 extern struct superswitch *version_to_superswitch(char *vers);
 
-extern int mdmon_running(int devnum);
-extern int mdmon_pid(int devnum);
+extern int mdmon_running(char *devnm);
+extern int mdmon_pid(char *devnm);
 extern int check_env(char *name);
 extern __u32 random32(void);
-extern int start_mdmon(int devnum);
+extern int start_mdmon(char *devnm);
 
 extern int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
 			 struct supertype *st, unsigned long stripes,
@@ -1305,26 +1307,9 @@ extern int child_monitor(int afd, struct mdinfo *sra, struct reshape *reshape,
 			 int dests, int *destfd, unsigned long long *destoffsets);
 void abort_reshape(struct mdinfo *sra);
 
-extern char *devnum2devname(int num);
 extern void fmt_devname(char *name, int num);
-extern int devname2devnum(char *name);
-extern int stat2devnum(struct stat *st);
-extern int fd2devnum(int fd);
-
-static inline int dev2major(int d)
-{
-	if (d >= 0)
-		return MD_MAJOR;
-	else
-		return get_mdp_major();
-}
-
-static inline int dev2minor(int d)
-{
-	if (d >= 0)
-		return d;
-	return (-1-d) << MdpMinorShift;
-}
+extern char *stat2devnm(struct stat *st);
+extern char *fd2devnm(int fd);
 
 #define _ROUND_UP(val, base)	(((val) + (base) - 1) & ~(base - 1))
 #define ROUND_UP(val, base)	_ROUND_UP(val, (typeof(val))(base))
diff --git a/mdmon.c b/mdmon.c
index 007071be..fd136e50 100644
--- a/mdmon.c
+++ b/mdmon.c
@@ -277,13 +277,12 @@ void usage(void)
 	exit(2);
 }
 
-static int mdmon(char *devname, int devnum, int must_fork, int takeover);
+static int mdmon(char *devnm, int must_fork, int takeover);
 
 int main(int argc, char *argv[])
 {
 	char *container_name = NULL;
-	int devnum;
-	char *devname;
+	char *devnm = NULL;
 	int status = 0;
 	int opt;
 	int all = 0;
@@ -349,47 +348,39 @@ int main(int argc, char *argv[])
 			if (e->metadata_version &&
 			    strncmp(e->metadata_version, "external:", 9) == 0 &&
 			    !is_subarray(&e->metadata_version[9])) {
-				devname = devnum2devname(e->devnum);
 				/* update cmdline so this mdmon instance can be
 				 * distinguished from others in a call to ps(1)
 				 */
-				if (strlen(devname) <= (unsigned)container_len) {
+				if (strlen(e->devnm) <= (unsigned)container_len) {
 					memset(container_name, 0, container_len);
-					sprintf(container_name, "%s", devname);
+					sprintf(container_name, "%s", e->devnm);
 				}
-				status |= mdmon(devname, e->devnum, 1,
-						takeover);
+				status |= mdmon(e->devnm, 1, takeover);
 			}
 		}
 		free_mdstat(mdstat);
 
 		return status;
 	} else if (strncmp(container_name, "md", 2) == 0) {
-		devnum = devname2devnum(container_name);
-		devname = devnum2devname(devnum);
-		if (strcmp(container_name, devname) != 0)
-			devname = NULL;
+		int id = devnm2devid(container_name);
+		if (id)
+			devnm = container_name;
 	} else {
 		struct stat st;
 
-		devnum = NoMdDev;
 		if (stat(container_name, &st) == 0)
-			devnum = stat2devnum(&st);
-		if (devnum == NoMdDev)
-			devname = NULL;
-		else
-			devname = devnum2devname(devnum);
+			devnm = xstrdup(stat2devnm(&st));
 	}
 
-	if (!devname) {
+	if (!devnm) {
 		fprintf(stderr, "mdmon: %s is not a valid md device name\n",
 			container_name);
 		exit(1);
 	}
-	return mdmon(devname, devnum, dofork && do_fork(), takeover);
+	return mdmon(devnm, dofork && do_fork(), takeover);
 }
 
-static int mdmon(char *devname, int devnum, int must_fork, int takeover)
+static int mdmon(char *devnm, int must_fork, int takeover)
 {
 	int mdfd;
 	struct mdinfo *mdi, *di;
@@ -402,17 +393,17 @@ static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 	pid_t victim = -1;
 	int victim_sock = -1;
 
-	dprintf("starting mdmon for %s\n", devname);
+	dprintf("starting mdmon for %s\n", devnm);
 
-	mdfd = open_dev(devnum);
+	mdfd = open_dev(devnm);
 	if (mdfd < 0) {
-		fprintf(stderr, "mdmon: %s: %s\n", devname,
+		fprintf(stderr, "mdmon: %s: %s\n", devnm,
 			strerror(errno));
 		return 1;
 	}
 	if (md_get_version(mdfd) < 0) {
 		fprintf(stderr, "mdmon: %s: Not an md device\n",
-			devname);
+			devnm);
 		return 1;
 	}
 
@@ -442,39 +433,33 @@ static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 		pfd[0] = pfd[1] = -1;
 
 	container = xcalloc(1, sizeof(*container));
-	container->devnum = devnum;
-	container->devname = devname;
+	strcpy(container->devnm, devnm);
 	container->arrays = NULL;
 	container->sock = -1;
 
-	if (!container->devname) {
-		fprintf(stderr, "mdmon: failed to allocate container name string\n");
-		exit(3);
-	}
-
-	mdi = sysfs_read(mdfd, container->devnum, GET_VERSION|GET_LEVEL|GET_DEVS);
+	mdi = sysfs_read(mdfd, container->devnm, GET_VERSION|GET_LEVEL|GET_DEVS);
 
 	if (!mdi) {
 		fprintf(stderr, "mdmon: failed to load sysfs info for %s\n",
-			container->devname);
+			container->devnm);
 		exit(3);
 	}
 	if (mdi->array.level != UnSet) {
 		fprintf(stderr, "mdmon: %s is not a container - cannot monitor\n",
-			devname);
+			devnm);
 		exit(3);
 	}
 	if (mdi->array.major_version != -1 ||
 	    mdi->array.minor_version != -2) {
 		fprintf(stderr, "mdmon: %s does not use external metadata - cannot monitor\n",
-			devname);
+			devnm);
 		exit(3);
 	}
 
 	container->ss = version_to_superswitch(mdi->text_version);
 	if (container->ss == NULL) {
 		fprintf(stderr, "mdmon: %s uses unsupported metadata: %s\n",
-			devname, mdi->text_version);
+			devnm, mdi->text_version);
 		exit(3);
 	}
 
@@ -502,23 +487,23 @@ static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 	act.sa_handler = SIG_IGN;
 	sigaction(SIGPIPE, &act, NULL);
 
-	victim = mdmon_pid(container->devnum);
+	victim = mdmon_pid(container->devnm);
 	if (victim >= 0)
-		victim_sock = connect_monitor(container->devname);
+		victim_sock = connect_monitor(container->devnm);
 
 	ignore = chdir("/");
 	if (!takeover && victim > 0 && victim_sock >= 0) {
 		if (fping_monitor(victim_sock) == 0) {
 			fprintf(stderr, "mdmon: %s already managed\n",
-				container->devname);
+				container->devnm);
 			exit(3);
 		}
 		close(victim_sock);
 		victim_sock = -1;
 	}
-	if (container->ss->load_container(container, mdfd, devname)) {
+	if (container->ss->load_container(container, mdfd, devnm)) {
 		fprintf(stderr, "mdmon: Cannot load metadata for %s\n",
-			devname);
+			devnm);
 		exit(3);
 	}
 	close(mdfd);
@@ -526,11 +511,11 @@ static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 	/* Ok, this is close enough.  We can say goodbye to our parent now.
 	 */
 	if (victim > 0)
-		remove_pidfile(devname);
-	if (make_pidfile(devname) < 0) {
+		remove_pidfile(devnm);
+	if (make_pidfile(devnm) < 0) {
 		exit(3);
 	}
-	container->sock = make_control_sock(devname);
+	container->sock = make_control_sock(devnm);
 
 	status = 0;
 	if (write(pfd[1], &status, sizeof(status)) < 0)
@@ -547,7 +532,7 @@ static int mdmon(char *devname, int devnum, int must_fork, int takeover)
 	}
 
 	if (victim > 0) {
-		try_kill_monitor(victim, container->devname, victim_sock);
+		try_kill_monitor(victim, container->devnm, victim_sock);
 		if (victim_sock >= 0)
 			close(victim_sock);
 	}
diff --git a/mdmon.h b/mdmon.h
index 59e1b537..21cf71d5 100644
--- a/mdmon.h
+++ b/mdmon.h
@@ -48,8 +48,6 @@ struct active_array {
 
 	int check_degraded; /* flag set by mon, read by manage */
 	int check_reshape; /* flag set by mon, read by manage */
-
-	int devnum;
 };
 
 /*
diff --git a/mdopen.c b/mdopen.c
index 462743c4..856b5c04 100644
--- a/mdopen.c
+++ b/mdopen.c
@@ -145,6 +145,7 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 	int parts;
 	char *cname;
 	char devname[20];
+	char devnm[32];
 	char cbuf[400];
 	if (chosen == NULL)
 		chosen = cbuf;
@@ -252,30 +253,31 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 		num = strtoul(n2, &ep, 10);
 		if (ep == n2 || *ep)
 			num = -1;
-		else if (mddev_busy(use_mdp ? (-1-num) : num))
-			num = -1;
+		else {
+			sprintf(devnm, "md%s%d", use_mdp ? "_d":"", num);
+			if (mddev_busy(devnm))
+				num = -1;
+		}
 	}
 
 	if (num < 0) {
 		/* need to choose a free number. */
-		num = find_free_devnum(use_mdp);
-		if (num == NoMdDev) {
+		char *_devnm = find_free_devnm(use_mdp);
+		if (devnm == NULL) {
 			pr_err("No avail md devices - aborting\n");
 			return -1;
 		}
+		strcpy(devnm, _devnm);
 	} else {
-		num = use_mdp ? (-1-num) : num;
-		if (mddev_busy(num)) {
+		sprintf(devnm, "%s%d", use_mdp?"md_d":"md", num);
+		if (mddev_busy(devnm)) {
 			pr_err("%s is already in use.\n",
 				dev);
 			return -1;
 		}
 	}
 
-	if (num < 0)
-		sprintf(devname, "/dev/md_d%d", -1-num);
-	else
-		sprintf(devname, "/dev/md%d", num);
+	sprintf(devname, "/dev/%s", devnm);
 
 	if (cname[0] == 0 && name) {
 		/* Need to find a name if we can
@@ -335,14 +337,14 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 		if (lstat(devname, &stb) == 0) {
 			/* Must be the correct device, else error */
 			if ((stb.st_mode&S_IFMT) != S_IFBLK ||
-			    stb.st_rdev != makedev(dev2major(num),dev2minor(num))) {
+			    stb.st_rdev != (dev_t)devnm2devid(devnm)) {
 				pr_err("%s exists but looks wrong, please fix\n",
 					devname);
 				return -1;
 			}
 		} else {
 			if (mknod(devname, S_IFBLK|0600,
-				  makedev(dev2major(num),dev2minor(num))) != 0) {
+				  devnm2devid(devnm)) != 0) {
 				pr_err("failed to create %s\n",
 					devname);
 				return -1;
@@ -389,7 +391,7 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 				make_parts(chosen, parts);
 		}
 	}
-	mdfd = open_dev_excl(num);
+	mdfd = open_dev_excl(devnm);
 	if (mdfd < 0)
 		pr_err("unexpected failure opening %s\n",
 			devname);
diff --git a/mdstat.c b/mdstat.c
index 5f690e5d..9ebfc075 100644
--- a/mdstat.c
+++ b/mdstat.c
@@ -152,9 +152,8 @@ struct mdstat_ent *mdstat_read(int hold, int start)
 	for (; (line = conf_line(f)) ; free_line(line)) {
 		struct mdstat_ent *ent;
 		char *w;
-		int devnum;
+		char devnm[32];
 		int in_devs = 0;
-		char *ep;
 
 		if (strcmp(line, "Personalities")==0)
 			continue;
@@ -164,18 +163,10 @@ struct mdstat_ent *mdstat_read(int hold, int start)
 			continue;
 		insert_here = NULL;
 		/* Better be an md line.. */
-		if (strncmp(line, "md", 2)!= 0)
+		if (strncmp(line, "md", 2)!= 0 || strlen(line) >= 32
+		    || (line[2] != '_' && !isdigit(line[2])))
 			continue;
-		if (strncmp(line, "md_d", 4) == 0)
-			devnum = -1-strtoul(line+4, &ep, 10);
-		else if (strncmp(line, "md", 2) == 0)
-			devnum = strtoul(line+2, &ep, 10);
-		else
-			continue;
-		if (ep == NULL || *ep ) {
-			/* pr_err("bad /proc/mdstat line starts: %s\n", line); */
-			continue;
-		}
+		strcpy(devnm, line);
 
 		ent = xmalloc(sizeof(*ent));
 		ent->dev = ent->level = ent->pattern= NULL;
@@ -189,7 +180,7 @@ struct mdstat_ent *mdstat_read(int hold, int start)
 		ent->members = NULL;
 
 		ent->dev = xstrdup(line);
-		ent->devnum = devnum;
+		strcpy(ent->devnm, devnm);
 
 		for (w=dl_next(line); w!= line ; w=dl_next(w)) {
 			int l = strlen(w);
@@ -207,19 +198,20 @@ struct mdstat_ent *mdstat_read(int hold, int start)
 			} else if (in_devs && strcmp(w, "blocks")==0)
 				in_devs = 0;
 			else if (in_devs) {
+				char *ep = strchr(w, '[');
 				ent->devcnt +=
 					add_member_devname(&ent->members, w);
-				if (strncmp(w, "md", 2)==0) {
+				if (ep && strncmp(w, "md", 2)==0) {
 					/* This has an md device as a component.
 					 * If that device is already in the
 					 * list, make sure we insert before
 					 * there.
 					 */
 					struct mdstat_ent **ih;
-					int dn2 = devname2devnum(w);
 					ih = &all;
 					while (ih != insert_here && *ih &&
-					       (*ih)->devnum != dn2)
+					       ((int)strlen((*ih)->devnm) != ep-w
+						|| strncmp((*ih)->devnm, w, ep-w) != 0))
 						ih = & (*ih)->next;
 					insert_here = ih;
 				}
@@ -345,13 +337,13 @@ void mdstat_wait_fd(int fd, const sigset_t *sigmask)
 		NULL, sigmask);
 }
 
-int mddev_busy(int devnum)
+int mddev_busy(char *devnm)
 {
 	struct mdstat_ent *mdstat = mdstat_read(0, 0);
 	struct mdstat_ent *me;
 
 	for (me = mdstat ; me ; me = me->next)
-		if (me->devnum == devnum)
+		if (strcmp(me->devnm, devnm) == 0)
 			break;
 	free_mdstat(mdstat);
 	return me != NULL;
@@ -384,35 +376,34 @@ struct mdstat_ent *mdstat_by_component(char *name)
 	return NULL;
 }
 
-struct mdstat_ent *mdstat_by_subdev(char *subdev, int container)
+struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container)
 {
 	struct mdstat_ent *mdstat = mdstat_read(0, 0);
+	struct mdstat_ent *ent = NULL;
 
 	while (mdstat) {
-		struct mdstat_ent *ent;
-		char *pos;
 		/* metadata version must match:
-		 *   external:[/-]md%d/%s
-		 * where %d is 'container' and %s is 'subdev'
+		 *   external:[/-]%s/%s
+		 * where first %s is 'container' and second %s is 'subdev'
 		 */
-		if (mdstat->metadata_version &&
-		    strncmp(mdstat->metadata_version, "external:", 9) == 0 &&
-		    strchr("/-", mdstat->metadata_version[9]) != NULL &&
-		    strncmp(mdstat->metadata_version+10, "md", 2) == 0 &&
-		    strtoul(mdstat->metadata_version+12, &pos, 10)
-		    == (unsigned)container &&
-		    pos > mdstat->metadata_version+12 &&
-		    *pos == '/' &&
-		    strcmp(pos+1, subdev) == 0
-			) {
-			free_mdstat(mdstat->next);
-			mdstat->next = NULL;
-			return mdstat;
-		}
+		if (ent)
+			free_mdstat(ent);
 		ent = mdstat;
 		mdstat = mdstat->next;
 		ent->next = NULL;
-		free_mdstat(ent);
+
+		if (ent->metadata_version == NULL ||
+		    strncmp(ent->metadata_version, "external:", 9) != 0)
+			continue;
+
+		if (!metadata_container_matches(ent->metadata_version+9,
+					       container) ||
+		    !metadata_subdev_matches(ent->metadata_version+9,
+					     subdev))
+			continue;
+
+		free_mdstat(mdstat);
+		return ent;
 	}
 	return NULL;
 }
diff --git a/monitor.c b/monitor.c
index c987d107..e034a6a0 100644
--- a/monitor.c
+++ b/monitor.c
@@ -573,9 +573,9 @@ static int wait_and_act(struct supertype *container, int nowait)
 		 */
 		int fd;
 		if (sigterm)
-			fd = open_dev_excl(container->devnum);
+			fd = open_dev_excl(container->devnm);
 		else
-			fd = open_dev_flags(container->devnum, O_RDONLY|O_EXCL);
+			fd = open_dev_flags(container->devnm, O_RDONLY|O_EXCL);
 		if (fd >= 0 || errno != EBUSY) {
 			/* OK, we are safe to leave */
 			if (sigterm && !dirty_arrays)
@@ -586,7 +586,7 @@ static int wait_and_act(struct supertype *container, int nowait)
 				/* On SIGTERM, someone (the take-over mdmon) will
 				 * clean up
 				 */
-				remove_pidfile(container->devname);
+				remove_pidfile(container->devnm);
 			exit_now = 1;
 			signal_manager();
 			close(fd);
diff --git a/msg.c b/msg.c
index 70cefe8f..776b29be 100644
--- a/msg.c
+++ b/msg.c
@@ -216,20 +216,6 @@ int ping_monitor(char *devname)
 	return err;
 }
 
-/* ping monitor using device number */
-int ping_monitor_by_id(int devnum)
-{
-	int err = -1;
-	char *container = devnum2devname(devnum);
-
-	if (container) {
-		err = ping_monitor(container);
-		free(container);
-	}
-
-	return err;
-}
-
 static char *ping_monitor_version(char *devname)
 {
 	int sfd = connect_monitor(devname);
@@ -291,9 +277,8 @@ int block_subarray(struct mdinfo *sra)
 int check_mdmon_version(char *container)
 {
 	char *version = NULL;
-	int devnum = devname2devnum(container);
 
-	if (!mdmon_running(devnum)) {
+	if (!mdmon_running(container)) {
 		/* if mdmon is not active we assume that any instance that is
 		 * later started will match the current mdadm version, if this
 		 * assumption is violated we may inadvertantly rebuild an array
@@ -357,7 +342,7 @@ int block_monitor(char *container, const int freeze)
 		if (!is_container_member(e, container))
 			continue;
 		sysfs_free(sra);
-		sra = sysfs_read(-1, e->devnum, GET_VERSION);
+		sra = sysfs_read(-1, e->devnm, GET_VERSION);
 		if (!sra) {
 			pr_err("failed to read sysfs for subarray%s\n",
 			       to_subarray(e, container));
@@ -393,7 +378,7 @@ int block_monitor(char *container, const int freeze)
 		 * or part-spares
 		 */
 		sysfs_free(sra);
-		sra = sysfs_read(-1, e->devnum, GET_DEVS | GET_STATE);
+		sra = sysfs_read(-1, e->devnm, GET_DEVS | GET_STATE);
 		if (sra && sra->array.spare_disks > 0) {
 			unblock_subarray(sra, freeze);
 			break;
@@ -409,7 +394,7 @@ int block_monitor(char *container, const int freeze)
 			if (!is_container_member(e2, container))
 				continue;
 			sysfs_free(sra);
-			sra = sysfs_read(-1, e2->devnum, GET_VERSION);
+			sra = sysfs_read(-1, e2->devnm, GET_VERSION);
 			if (unblock_subarray(sra, freeze))
 				pr_err("Failed to unfreeze %s\n", e2->dev);
 		}
@@ -441,7 +426,7 @@ void unblock_monitor(char *container, const int unfreeze)
 		if (!is_container_member(e, container))
 			continue;
 		sysfs_free(sra);
-		sra = sysfs_read(-1, e->devnum, GET_VERSION|GET_LEVEL);
+		sra = sysfs_read(-1, e->devnm, GET_VERSION|GET_LEVEL);
 		if (!sra)
 			continue;
 		if (sra->array.level > 0)
@@ -456,8 +441,6 @@ void unblock_monitor(char *container, const int unfreeze)
 	free_mdstat(ent);
 }
 
-
-
 /* give the manager a chance to view the updated container state.  This
  * would naturally happen due to the manager noticing a change in
  * /proc/mdstat; however, pinging encourages this detection to happen
diff --git a/msg.h b/msg.h
index eefa6495..7306bcab 100644
--- a/msg.h
+++ b/msg.h
@@ -27,7 +27,6 @@ extern int ack(int fd, int tmo);
 extern int wait_reply(int fd, int tmo);
 extern int connect_monitor(char *devname);
 extern int ping_monitor(char *devname);
-extern int ping_monitor_by_id(int devnum);
 extern int block_subarray(struct mdinfo *sra);
 extern int unblock_subarray(struct mdinfo *sra, const int unfreeze);
 extern int block_monitor(char *container, const int freeze);
diff --git a/policy.c b/policy.c
index c3de692e..48eed6c8 100644
--- a/policy.c
+++ b/policy.c
@@ -421,7 +421,7 @@ struct dev_policy *disk_policy(struct mdinfo *disk)
 	return pol;
 }
 
-struct dev_policy *devnum_policy(int dev)
+struct dev_policy *devid_policy(int dev)
 {
 	struct mdinfo disk;
 	disk.disk.major = major(dev);
@@ -677,9 +677,9 @@ int domain_test(struct domainlist *dom, struct dev_policy *pol,
 	return found_any;
 }
 
-void domainlist_add_dev(struct domainlist **dom, int devnum, const char *metadata)
+void domainlist_add_dev(struct domainlist **dom, int devid, const char *metadata)
 {
-	struct dev_policy *pol = devnum_policy(devnum);
+	struct dev_policy *pol = devid_policy(devid);
 	domain_merge(dom, pol, metadata);
 	dev_policy_free(pol);
 }
diff --git a/super-ddf.c b/super-ddf.c
index 3b3c1f0f..c0fd5fae 100644
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -884,7 +884,6 @@ static struct supertype *match_metadata_desc_ddf(char *arg)
 		return NULL;
 
 	st = xcalloc(1, sizeof(*st));
-	st->container_dev = NoMdDev;
 	st->ss = &super_ddf;
 	st->max_devs = 512;
 	st->minor_version = 0;
@@ -1451,7 +1450,7 @@ static void getinfo_super_ddf_bvd(struct supertype *st, struct mdinfo *info, cha
 	info->array.major_version = -1;
 	info->array.minor_version = -2;
 	sprintf(info->text_version, "/%s/%d",
-		devnum2devname(st->container_dev),
+		st->container_devnm,
 		info->container_member);
 	info->safe_mode_delay = 200;
 
@@ -2676,7 +2675,7 @@ static int validate_geometry_ddf(struct supertype *st,
 	 */
 	fd = open(dev, O_RDONLY|O_EXCL, 0);
 	if (fd >= 0) {
-		sra = sysfs_read(fd, 0, GET_VERSION);
+		sra = sysfs_read(fd, NULL, GET_VERSION);
 		close(fd);
 		if (sra && sra->array.major_version == -1 &&
 		    strcmp(sra->text_version, "ddf") == 0) {
@@ -2708,7 +2707,7 @@ static int validate_geometry_ddf(struct supertype *st,
 			       dev, strerror(EBUSY));
 		return 0;
 	}
-	sra = sysfs_read(cfd, 0, GET_VERSION);
+	sra = sysfs_read(cfd, NULL, GET_VERSION);
 	close(fd);
 	if (sra && sra->array.major_version == -1 &&
 	    strcmp(sra->text_version, "ddf") == 0) {
@@ -2718,7 +2717,7 @@ static int validate_geometry_ddf(struct supertype *st,
 		struct ddf_super *ddf;
 		if (load_super_ddf_all(st, cfd, (void **)&ddf, NULL) == 0) {
 			st->sb = ddf;
-			st->container_dev = fd2devnum(cfd);
+			strcpy(st->container_devnm, fd2devnm(cfd));
 			close(cfd);
 			return validate_geometry_ddf_bvd(st, level, layout,
 							 raiddisks, chunk, size,
@@ -2937,7 +2936,7 @@ static int load_super_ddf_all(struct supertype *st, int fd,
 		st->minor_version = 0;
 		st->max_devs = 512;
 	}
-	st->container_dev = fd2devnum(fd);
+	strcpy(st->container_devnm, fd2devnm(fd));
 	return 0;
 }
 
@@ -3020,8 +3019,7 @@ static struct mdinfo *container_content_ddf(struct supertype *st, char *subarray
 		ddf->currentconf = NULL;
 
 		sprintf(this->text_version, "/%s/%d",
-			devnum2devname(st->container_dev),
-			this->container_member);
+			st->container_devnm, this->container_member);
 
 		for (i = 0 ; i < ddf->mppe ; i++) {
 			struct mdinfo *dev;
diff --git a/super-intel.c b/super-intel.c
index 4c30b7e8..24016b7c 100644
--- a/super-intel.c
+++ b/super-intel.c
@@ -431,7 +431,7 @@ struct imsm_update_activate_spare {
 };
 
 struct geo_params {
-	int dev_id;
+	char devnm[32];
 	char *dev_name;
 	unsigned long long size;
 	int level;
@@ -605,7 +605,6 @@ static struct supertype *match_metadata_desc_imsm(char *arg)
 		return NULL;
 
 	st = xcalloc(1, sizeof(*st));
-	st->container_dev = NoMdDev;
 	st->ss = &super_imsm;
 	st->max_devs = IMSM_MAX_DEVICES;
 	st->minor_version = 0;
@@ -2532,7 +2531,6 @@ static void getinfo_super_imsm_volume(struct supertype *st, struct mdinfo *info,
 	struct imsm_map *prev_map = get_imsm_map(dev, MAP_1);
 	struct imsm_map *map_to_analyse = map;
 	struct dl *dl;
-	char *devname;
 	int map_disks = info->array.raid_disks;
 
 	memset(info, 0, sizeof(*info));
@@ -2694,11 +2692,7 @@ static void getinfo_super_imsm_volume(struct supertype *st, struct mdinfo *info,
 
 	info->array.major_version = -1;
 	info->array.minor_version = -2;
-	devname = devnum2devname(st->container_dev);
-	*info->text_version = '\0';
-	if (devname)
-		sprintf(info->text_version, "/%s/%d", devname, info->container_member);
-	free(devname);
+	sprintf(info->text_version, "/%s/%d", st->container_devnm, info->container_member);
 	info->safe_mode_delay = 4000;  /* 4 secs like the Matrix driver */
 	uuid_from_super_imsm(st, info->uuid);
 
@@ -4158,7 +4152,7 @@ imsm_thunderdome(struct intel_super **super_list, int len)
 
 static int
 get_sra_super_block(int fd, struct intel_super **super_list, char *devname, int *max, int keep_fd);
-static int get_super_block(struct intel_super **super_list, int devnum, char *devname,
+static int get_super_block(struct intel_super **super_list, char *devnm, char *devname,
 			   int major, int minor, int keep_fd);
 static int
 get_devlist_super_block(struct md_list *devlist, struct intel_super **super_list,
@@ -4233,9 +4227,9 @@ static int load_super_imsm_all(struct supertype *st, int fd, void **sbp,
 
 	*sbp = super;
 	if (fd >= 0)
-		st->container_dev = fd2devnum(fd);
+		strcpy(st->container_devnm, fd2devnm(fd));
 	else
-		st->container_dev = NoMdDev;
+		st->container_devnm[0] = 0;
 	if (err == 0 && st->ss == NULL) {
 		st->ss = &super_imsm;
 		st->minor_version = 0;
@@ -4278,7 +4272,7 @@ get_devlist_super_block(struct md_list *devlist, struct intel_super **super_list
 			int major = major(tmpdev->st_rdev);
 			int minor = minor(tmpdev->st_rdev);
 			err = get_super_block(super_list,
-					      -1,
+					      NULL,
 					      tmpdev->devname,
 					      major, minor,
 					      keep_fd);
@@ -4294,7 +4288,7 @@ get_devlist_super_block(struct md_list *devlist, struct intel_super **super_list
 	return err;
 }
 
-static int get_super_block(struct intel_super **super_list, int devnum, char *devname,
+static int get_super_block(struct intel_super **super_list, char *devnm, char *devname,
 			   int major, int minor, int keep_fd)
 {
 	struct intel_super*s = NULL;
@@ -4320,7 +4314,7 @@ static int get_super_block(struct intel_super **super_list, int devnum, char *de
 	err = load_and_parse_mpb(dfd, s, NULL, keep_fd);
 
 	/* retry the load if we might have raced against mdmon */
-	if (err == 3 && (devnum != -1) && mdmon_running(devnum))
+	if (err == 3 && devnm && mdmon_running(devnm))
 		for (retry = 0; retry < 3; retry++) {
 			usleep(3000);
 			err = load_and_parse_mpb(dfd, s, NULL, keep_fd);
@@ -4347,11 +4341,11 @@ static int
 get_sra_super_block(int fd, struct intel_super **super_list, char *devname, int *max, int keep_fd)
 {
 	struct mdinfo *sra;
-	int devnum;
+	char *devnm;
 	struct mdinfo *sd;
 	int err = 0;
 	int i = 0;
-	sra = sysfs_read(fd, 0, GET_LEVEL|GET_VERSION|GET_DEVS|GET_STATE);
+	sra = sysfs_read(fd, NULL, GET_LEVEL|GET_VERSION|GET_DEVS|GET_STATE);
 	if (!sra)
 		return 1;
 
@@ -4362,9 +4356,9 @@ get_sra_super_block(int fd, struct intel_super **super_list, char *devname, int
 		goto error;
 	}
 	/* load all mpbs */
-	devnum = fd2devnum(fd);
+	devnm = fd2devnm(fd);
 	for (sd = sra->devs, i = 0; sd; sd = sd->next, i++) {
-		if (get_super_block(super_list, devnum, devname,
+		if (get_super_block(super_list, devnm, devname,
 				    sd->disk.major, sd->disk.minor, keep_fd) != 0) {
 			err = 7;
 			goto error;
@@ -6230,7 +6224,7 @@ static int validate_geometry_imsm(struct supertype *st, int level, int layout,
 				dev);
 		return 0;
 	}
-	sra = sysfs_read(cfd, 0, GET_VERSION);
+	sra = sysfs_read(cfd, NULL, GET_VERSION);
 	if (sra && sra->array.major_version == -1 &&
 	    strcmp(sra->text_version, "imsm") == 0)
 		is_member = 1;
@@ -6243,7 +6237,7 @@ static int validate_geometry_imsm(struct supertype *st, int level, int layout,
 
 		if (load_super_imsm_all(st, cfd, (void **) &super, NULL, NULL, 1) == 0) {
 			st->sb = super;
-			st->container_dev = fd2devnum(cfd);
+			strcpy(st->container_devnm, fd2devnm(cfd));
 			close(cfd);
 			return validate_geometry_imsm_volume(st, level, layout,
 							     raiddisks, chunk,
@@ -6301,7 +6295,7 @@ static int kill_subarray_imsm(struct supertype *st)
 		if (i < current_vol)
 			continue;
 		sprintf(subarray, "%u", i);
-		if (is_subarray_active(subarray, st->devname)) {
+		if (is_subarray_active(subarray, st->devnm)) {
 			pr_err("deleting subarray-%d would change the UUID of active subarray-%d, aborting\n",
 			       current_vol, i);
 
@@ -6357,7 +6351,7 @@ static int update_subarray_imsm(struct supertype *st, char *subarray,
 		char *ep;
 		int vol;
 
-		if (is_subarray_active(subarray, st->devname)) {
+		if (is_subarray_active(subarray, st->devnm)) {
 			pr_err("Unable to update name of active subarray\n");
 			return 2;
 		}
@@ -9332,19 +9326,20 @@ static const char *imsm_get_disk_controller_domain(const char *path)
 	return drv;
 }
 
-static int imsm_find_array_minor_by_subdev(int subdev, int container, int *minor)
+static char *imsm_find_array_devnm_by_subdev(int subdev, char *container)
 {
+	static char devnm[32];
 	char subdev_name[20];
 	struct mdstat_ent *mdstat;
 
 	sprintf(subdev_name, "%d", subdev);
 	mdstat = mdstat_by_subdev(subdev_name, container);
 	if (!mdstat)
-		return -1;
+		return NULL;
 
-	*minor = mdstat->devnum;
+	strcpy(devnm, mdstat->devnm);
 	free_mdstat(mdstat);
-	return 0;
+	return devnm;
 }
 
 static int imsm_reshape_is_allowed_on_container(struct supertype *st,
@@ -9361,8 +9356,7 @@ static int imsm_reshape_is_allowed_on_container(struct supertype *st,
 	int devices_that_can_grow = 0;
 
 	dprintf("imsm: imsm_reshape_is_allowed_on_container(ENTER): "
-		"st->devnum = (%i)\n",
-		st->devnum);
+		"st->devnm = (%s)\n", st->devnm);
 
 	if (geo->size > 0 ||
 	    geo->level != UnSet ||
@@ -9382,8 +9376,7 @@ static int imsm_reshape_is_allowed_on_container(struct supertype *st,
 
 	info = container_content_imsm(st, NULL);
 	for (member = info; member; member = member->next) {
-		int result;
-		int minor;
+		char *result;
 
 		dprintf("imsm: checking device_num: %i\n",
 			member->container_member);
@@ -9440,10 +9433,9 @@ static int imsm_reshape_is_allowed_on_container(struct supertype *st,
 		 * so they need to be assembled.  We have already
 		 * checked that no recovery etc is happening.
 		 */
-		result = imsm_find_array_minor_by_subdev(member->container_member,
-							 st->container_dev,
-							 &minor);
-		if (result < 0) {
+		result = imsm_find_array_devnm_by_subdev(member->container_member,
+							 st->container_devnm);
+		if (result == NULL) {
 			dprintf("imsm: cannot find array\n");
 			break;
 		}
@@ -9819,8 +9811,8 @@ enum imsm_reshape_type imsm_analyze_change(struct supertype *st,
 		}
 		if ((super->current_vol + 1) != super->anchor->num_raid_devs) {
 			pr_err("Error. The last volume in container "
-			       "can be expanded only (%i/%i).\n",
-			       super->current_vol, st->devnum);
+			       "can be expanded only (%i/%s).\n",
+			       super->current_vol, st->devnm);
 			goto analyse_change_exit;
 		}
 		/* check the maximum available size
@@ -9959,7 +9951,7 @@ static int imsm_reshape_super(struct supertype *st, unsigned long long size,
 	memset(&geo, 0, sizeof(struct geo_params));
 
 	geo.dev_name = dev;
-	geo.dev_id = st->devnum;
+	strcpy(geo.devnm, st->devnm);
 	geo.size = size;
 	geo.level = level;
 	geo.layout = layout;
@@ -9974,7 +9966,7 @@ static int imsm_reshape_super(struct supertype *st, unsigned long long size,
 	if (experimental() == 0)
 		return ret_val;
 
-	if (st->container_dev == st->devnum) {
+	if (strcmp(st->container_devnm, st->devnm) == 0) {
 		/* On container level we can only increase number of devices. */
 		dprintf("imsm: info: Container operation\n");
 		int old_raid_disks = 0;
@@ -10013,19 +10005,20 @@ static int imsm_reshape_super(struct supertype *st, unsigned long long size,
 		 */
 		struct intel_super *super = st->sb;
 		struct intel_dev *dev = super->devlist;
-		int change, devnum;
+		int change;
 		dprintf("imsm: info: Volume operation\n");
 		/* find requested device */
 		while (dev) {
-			if (imsm_find_array_minor_by_subdev(
-				    dev->index, st->container_dev, &devnum) == 0
-			    && devnum == geo.dev_id)
+			char *devnm = 
+				imsm_find_array_devnm_by_subdev(
+					dev->index, st->container_devnm);
+			if (devnm && strcmp(devnm, geo.devnm) == 0)
 				break;
 			dev = dev->next;
 		}
 		if (dev == NULL) {
-			pr_err("Cannot find %s (%i) subarray\n",
-				geo.dev_name, geo.dev_id);
+			pr_err("Cannot find %s (%s) subarray\n",
+				geo.dev_name, geo.devnm);
 			goto exit_imsm_reshape_super;
 		}
 		super->current_vol = dev->index;
diff --git a/super0.c b/super0.c
index bc95fb66..1f4dc750 100644
--- a/super0.c
+++ b/super0.c
@@ -953,7 +953,7 @@ static struct supertype *match_metadata_desc0(char *arg)
 {
 	struct supertype *st = xcalloc(1, sizeof(*st));
 
-	st->container_dev = NoMdDev;
+	st->container_devnm[0] = 0;
 	st->ss = &super0;
 	st->info = NULL;
 	st->minor_version = 90;
diff --git a/super1.c b/super1.c
index 4e380d98..d0f1d5f0 100644
--- a/super1.c
+++ b/super1.c
@@ -1716,7 +1716,7 @@ static struct supertype *match_metadata_desc1(char *arg)
 {
 	struct supertype *st = xcalloc(1, sizeof(*st));
 
-	st->container_dev = NoMdDev;
+	st->container_devnm[0] = 0;
 	st->ss = &super1;
 	st->max_devs = MAX_DEVS;
 	st->sb = NULL;
diff --git a/sysfs.c b/sysfs.c
index b66cebf3..f9fb989d 100644
--- a/sysfs.c
+++ b/sysfs.c
@@ -57,16 +57,12 @@ void sysfs_free(struct mdinfo *sra)
 	}
 }
 
-int sysfs_open(int devnum, char *devname, char *attr)
+int sysfs_open(char *devnm, char *devname, char *attr)
 {
 	char fname[50];
 	int fd;
-	char *mdname = devnum2devname(devnum);
 
-	if (!mdname)
-		return -1;
-
-	sprintf(fname, "/sys/block/%s/md/", mdname);
+	sprintf(fname, "/sys/block/%s/md/", devnm);
 	if (devname) {
 		strcat(fname, devname);
 		strcat(fname, "/");
@@ -75,26 +71,25 @@ int sysfs_open(int devnum, char *devname, char *attr)
 	fd = open(fname, O_RDWR);
 	if (fd < 0 && errno == EACCES)
 		fd = open(fname, O_RDONLY);
-	free(mdname);
 	return fd;
 }
 
-void sysfs_init(struct mdinfo *mdi, int fd, int devnum)
+void sysfs_init(struct mdinfo *mdi, int fd, char *devnm)
 {
 	mdi->sys_name[0] = 0;
 	if (fd >= 0) {
 		mdu_version_t vers;
 		if (ioctl(fd, RAID_VERSION, &vers) != 0)
 			return;
-		devnum = fd2devnum(fd);
+		devnm = fd2devnm(fd);
 	}
-	if (devnum == NoMdDev)
+	if (devnm == NULL)
 		return;
-	fmt_devname(mdi->sys_name, devnum);
+	strcpy(mdi->sys_name, devnm);
 }
 
 
-struct mdinfo *sysfs_read(int fd, int devnum, unsigned long options)
+struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options)
 {
 	char fname[PATH_MAX];
 	char buf[PATH_MAX];
@@ -106,7 +101,7 @@ struct mdinfo *sysfs_read(int fd, int devnum, unsigned long options)
 	struct dirent *de;
 
 	sra = xcalloc(1, sizeof(*sra));
-	sysfs_init(sra, fd, devnum);
+	sysfs_init(sra, fd, devnm);
 	if (sra->sys_name[0] == 0) {
 		free(sra);
 		return NULL;
@@ -641,13 +636,7 @@ int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume)
 		return rv;
 
 	memset(nm, 0, sizeof(nm));
-	sprintf(dv, "/sys/dev/block/%d:%d", sd->disk.major, sd->disk.minor);
-	rv = readlink(dv, nm, sizeof(nm)-1);
-	if (rv <= 0)
-		return -1;
-	nm[rv] = '\0';
-	dname = strrchr(nm, '/');
-	if (dname) dname++;
+	dname = devid2devnm(makedev(sd->disk.major, sd->disk.minor));
 	strcpy(sd->sys_name, "dev-");
 	strcpy(sd->sys_name+4, dname);
 
@@ -779,12 +768,12 @@ int sysfs_disk_to_scsi_id(int fd, __u32 *id)
 }
 
 
-int sysfs_unique_holder(int devnum, long rdev)
+int sysfs_unique_holder(char *devnm, long rdev)
 {
-	/* Check that devnum is a holder of rdev,
+	/* Check that devnm is a holder of rdev,
 	 * and is the only holder.
 	 * we should be locked against races by
-	 * an O_EXCL on devnum
+	 * an O_EXCL on devnm
 	 * Return values:
 	 *  0 - not unique, not even a holder
 	 *  1 - unique, this is the only holder.
@@ -803,11 +792,9 @@ int sysfs_unique_holder(int devnum, long rdev)
 		return -1;
 	l = strlen(dirname);
 	while ((de = readdir(dir)) != NULL) {
-		char buf[10];
+		char buf[100];
+		char *sl;
 		int n;
-		int mj, mn;
-		char c;
-		int fd;
 
 		if (de->d_ino == 0)
 			continue;
@@ -815,24 +802,16 @@ int sysfs_unique_holder(int devnum, long rdev)
 			continue;
 		strcpy(dirname+l, "/");
 		strcat(dirname+l, de->d_name);
-		strcat(dirname+l, "/dev");
-		fd = open(dirname, O_RDONLY);
-		if (fd < 0) {
-			/* Probably a race, just ignore this */
-			continue;
-		}
-		n = read(fd, buf, sizeof(buf)-1);
-		close(fd);
-		if (n < 0)
+		n = readlink(dirname, buf, sizeof(buf)-1);
+		if (n <= 0)
 			continue;
 		buf[n] = 0;
-		if (sscanf(buf, "%d:%d%c", &mj, &mn, &c) != 3 ||
-		    c != '\n')
+		sl = strrchr(buf, '/');
+		if (!sl)
 			continue;
-		if (mj != MD_MAJOR)
-			mn = -1-(mn>>6);
+		sl++;
 
-		if (devnum == mn)
+		if (strcmp(devnm, sl) == 0)
 			ret |= 1;
 		else
 			ret |= 2;
diff --git a/util.c b/util.c
index 8817a3e2..a5eb8ed5 100644
--- a/util.c
+++ b/util.c
@@ -778,42 +778,79 @@ int get_data_disks(int level, int layout, int raid_disks)
 }
 
 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
-char *get_md_name(int dev)
+
+int devnm2devid(char *devnm)
+{
+	/* First look in /sys/block/$DEVNM/dev for %d:%d
+	 * If that fails, try parsing out a number
+	 */
+	char path[100];
+	char *ep;
+	int fd;
+	int mjr,mnr;
+
+	sprintf(path, "/sys/block/%s/dev", devnm);
+	fd = open(path, O_RDONLY);
+	if (fd >= 0) {
+		char buf[20];
+		int n = read(fd, buf, sizeof(buf));
+		close(fd);
+		if (n > 0)
+			buf[n] = 0;
+		if (n > 0 && sscanf(buf, "%d:%d\n", &mjr, &mnr) == 2)
+			return makedev(mjr, mnr);
+	}
+	if (strncmp(devnm, "md_d", 4) == 0 &&
+	    isdigit(devnm[4]) &&
+	    (mnr = strtoul(devnm+4, &ep, 10)) >= 0 &&
+	    ep > devnm && *ep == 0)
+		return makedev(get_mdp_major(), mnr << MdpMinorShift);
+
+	if (strncmp(devnm, "md", 2) == 0 &&
+	    isdigit(devnm[2]) &&
+	    (mnr = strtoul(devnm+2, &ep, 10)) >= 0 &&
+	    ep > devnm && *ep == 0)
+		return makedev(MD_MAJOR, mnr);
+
+	return 0;
+}
+
+char *get_md_name(char *devnm)
 {
 	/* find /dev/md%d or /dev/md/%d or make a device /dev/.tmp.md%d */
 	/* if dev < 0, want /dev/md/d%d or find mdp in /proc/devices ... */
+
 	static char devname[50];
 	struct stat stb;
-	dev_t rdev;
+	dev_t rdev = devnm2devid(devnm);
 	char *dn;
 
-	if (dev < 0) {
-		int mdp =  get_mdp_major();
-		if (mdp < 0) return NULL;
-		rdev = makedev(mdp, (-1-dev)<<6);
-		snprintf(devname, sizeof(devname), "/dev/md/d%d", -1-dev);
-		if (stat(devname, &stb) == 0
-		    && (S_IFMT&stb.st_mode) == S_IFBLK
-		    && (stb.st_rdev == rdev))
-			return devname;
-	} else {
-		rdev = makedev(MD_MAJOR, dev);
-		snprintf(devname, sizeof(devname), "/dev/md%d", dev);
-		if (stat(devname, &stb) == 0
-		    && (S_IFMT&stb.st_mode) == S_IFBLK
-		    && (stb.st_rdev == rdev))
-			return devname;
-
-		snprintf(devname, sizeof(devname), "/dev/md/%d", dev);
+	if (rdev == 0)
+		return 0;
+	if (strncmp(devnm, "md_", 3) == 0) {
+		snprintf(devname, sizeof(devname), "/dev/md/%s",
+			devnm + 3);
 		if (stat(devname, &stb) == 0
 		    && (S_IFMT&stb.st_mode) == S_IFBLK
 		    && (stb.st_rdev == rdev))
 			return devname;
 	}
+	snprintf(devname, sizeof(devname), "/dev/%s", devnm);
+	if (stat(devname, &stb) == 0
+	    && (S_IFMT&stb.st_mode) == S_IFBLK
+	    && (stb.st_rdev == rdev))
+		return devname;
+
+	snprintf(devname, sizeof(devname), "/dev/md/%s", devnm+2);
+	if (stat(devname, &stb) == 0
+	    && (S_IFMT&stb.st_mode) == S_IFBLK
+	    && (stb.st_rdev == rdev))
+		return devname;
+
 	dn = map_dev(major(rdev), minor(rdev), 0);
 	if (dn)
 		return dn;
-	snprintf(devname, sizeof(devname), "/dev/.tmp.md%d", dev);
+	snprintf(devname, sizeof(devname), "/dev/.tmp.%s", devnm);
 	if (mknod(devname, S_IFBLK | 0600, rdev) == -1)
 		if (errno != EEXIST)
 			return NULL;
@@ -832,33 +869,37 @@ void put_md_name(char *name)
 		unlink(name);
 }
 
-int find_free_devnum(int use_partitions)
+char *find_free_devnm(int use_partitions)
 {
+	static char devnm[32];
 	int devnum;
 	for (devnum = 127; devnum != 128;
 	     devnum = devnum ? devnum-1 : (1<<20)-1) {
-		int _devnum;
-		char nbuf[50];
 
-		_devnum = use_partitions ? (-1-devnum) : devnum;
-		if (mddev_busy(_devnum))
+		if (use_partitions)
+			sprintf(devnm, "md_d%d", devnum);
+		else
+			sprintf(devnm, "md%d", devnum);
+		if (mddev_busy(devnm))
 			continue;
-		sprintf(nbuf, "%s%d", use_partitions?"mdp":"md", devnum);
-		if (!conf_name_is_free(nbuf))
+		if (!conf_name_is_free(devnm))
 			continue;
 		if (!use_udev()) {
 			/* make sure it is new to /dev too, at least as a
 			 * non-standard */
-			char *dn = map_dev(dev2major(_devnum),
-					   dev2minor(_devnum), 0);
-			if (dn && ! is_standard(dn, NULL))
-				continue;
+			int devid = devnm2devid(devnm);
+			if (devid) {
+				char *dn = map_dev(major(devid),
+						   minor(devid), 0);
+				if (dn && ! is_standard(dn, NULL))
+					continue;
+			}
 		}
 		break;
 	}
 	if (devnum == 128)
-		return NoMdDev;
-	return use_partitions ? (-1-devnum) : devnum;
+		return NULL;
+	return devnm;
 }
 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 
@@ -900,26 +941,29 @@ int dev_open(char *dev, int flags)
 	return fd;
 }
 
-int open_dev_flags(int devnum, int flags)
+int open_dev_flags(char *devnm, int flags)
 {
+	int devid;
 	char buf[20];
 
-	sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
+	devid = devnm2devid(devnm);
+	sprintf(buf, "%d:%d", major(devid), minor(devid));
 	return dev_open(buf, flags);
 }
 
-int open_dev(int devnum)
+int open_dev(char *devnm)
 {
-	return open_dev_flags(devnum, O_RDONLY);
+	return open_dev_flags(devnm, O_RDONLY);
 }
 
-int open_dev_excl(int devnum)
+int open_dev_excl(char *devnm)
 {
 	char buf[20];
 	int i;
 	int flags = O_RDWR;
+	int devid = devnm2devid(devnm);
 
-	sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
+	sprintf(buf, "%d:%d", major(devid), minor(devid));
 	for (i = 0 ; i < 25 ; i++) {
 		int fd = dev_open(buf, flags|O_EXCL);
 		if (fd >= 0)
@@ -990,9 +1034,9 @@ struct supertype *super_by_fd(int fd, char **subarrayp)
 	char version[20];
 	int i;
 	char *subarray = NULL;
-	int container = NoMdDev;
+	char container[32] = "";
 
-	sra = sysfs_read(fd, 0, GET_VERSION);
+	sra = sysfs_read(fd, NULL, GET_VERSION);
 
 	if (sra) {
 		vers = sra->array.major_version;
@@ -1018,7 +1062,7 @@ struct supertype *super_by_fd(int fd, char **subarrayp)
 			*subarray++ = '\0';
 			subarray = xstrdup(subarray);
 		}
-		container = devname2devnum(dev);
+		strcpy(container, dev);
 		if (sra)
 			sysfs_free(sra);
 		sra = sysfs_read(-1, container, GET_VERSION);
@@ -1037,8 +1081,8 @@ struct supertype *super_by_fd(int fd, char **subarrayp)
 		st->sb = NULL;
 		if (subarrayp)
 			*subarrayp = subarray;
-		st->container_dev = container;
-		st->devnum = fd2devnum(fd);
+		strcpy(st->container_devnm, container);
+		strcpy(st->devnm, fd2devnm(fd));
 	} else
 		free(subarray);
 
@@ -1091,7 +1135,7 @@ struct supertype *guess_super_type(int fd, enum guess_types guess_type)
 	int i;
 
 	st = xcalloc(1, sizeof(*st));
-	st->container_dev = NoMdDev;
+	st->container_devnm[0] = 0;
 
 	for (i = 0 ; superlist[i]; i++) {
 		int rv;
@@ -1386,13 +1430,47 @@ struct superswitch *version_to_superswitch(char *vers)
 	return NULL;
 }
 
+int metadata_container_matches(char *metadata, char *devnm)
+{
+	/* Check if 'devnm' is the container named in 'metadata'
+	 * which is
+	 *   /containername/componentname  or
+	 *   -containername/componentname
+	 */
+	int l;
+	if (*metadata != '/' && *metadata != '-')
+		return 0;
+	l = strlen(devnm);
+	if (strncmp(metadata+1, devnm, l) != 0)
+		return 0;
+	if (metadata[l+1] != '/')
+		return 0;
+	return 1;
+}
+
+int metadata_subdev_matches(char *metadata, char *devnm)
+{
+	/* Check if 'devnm' is the subdev named in 'metadata'
+	 * which is
+	 *   /containername/subdev  or
+	 *   -containername/subdev
+	 */
+	char *sl;
+	if (*metadata != '/' && *metadata != '-')
+		return 0;
+	sl = strchr(metadata+1, '/');
+	if (!sl)
+		return 0;
+	if (strcmp(sl+1, devnm) == 0)
+		return 1;
+	return 0;
+}
+
 int is_container_member(struct mdstat_ent *mdstat, char *container)
 {
 	if (mdstat->metadata_version == NULL ||
 	    strncmp(mdstat->metadata_version, "external:", 9) != 0 ||
-	    !is_subarray(mdstat->metadata_version+9) ||
-	    strncmp(mdstat->metadata_version+10, container, strlen(container)) != 0 ||
-	    mdstat->metadata_version[10+strlen(container)] != '/')
+	    !metadata_container_matches(mdstat->metadata_version+9, container))
 		return 0;
 
 	return 1;
@@ -1425,6 +1503,7 @@ int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet)
 	struct mdinfo *mdi;
 	struct mdinfo *info;
 	int fd, err = 1;
+	char *_devnm;
 
 	fd = open(dev, O_RDWR|O_EXCL);
 	if (fd < 0) {
@@ -1434,15 +1513,16 @@ int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet)
 		return -1;
 	}
 
-	st->devnum = fd2devnum(fd);
-	if (st->devnum == NoMdDev) {
+	_devnm = fd2devnm(fd);
+	if (_devnm == NULL) {
 		if (!quiet)
 			pr_err("Failed to determine device number for %s\n",
 			       dev);
 		goto close_fd;
 	}
+	strcpy(st->devnm, _devnm);
 
-	mdi = sysfs_read(fd, st->devnum, GET_VERSION|GET_LEVEL);
+	mdi = sysfs_read(fd, st->devnm, GET_VERSION|GET_LEVEL);
 	if (!mdi) {
 		if (!quiet)
 			pr_err("Failed to read sysfs for %s\n",
@@ -1464,8 +1544,7 @@ int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet)
 		goto free_sysfs;
 	}
 
-	st->devname = devnum2devname(st->devnum);
-	if (!st->devname) {
+	if (st->devnm[0] == 0) {
 		if (!quiet)
 			pr_err("Failed to allocate device name\n");
 		goto free_sysfs;
@@ -1474,14 +1553,14 @@ int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet)
 	if (!st->ss->load_container) {
 		if (!quiet)
 			pr_err("%s is not a container\n", dev);
-		goto free_name;
+		goto free_sysfs;
 	}
 
 	if (st->ss->load_container(st, fd, NULL)) {
 		if (!quiet)
 			pr_err("Failed to load metadata for %s\n",
 				dev);
-		goto free_name;
+		goto free_sysfs;
 	}
 
 	info = st->ss->container_content(st, subarray);
@@ -1498,9 +1577,6 @@ int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet)
  free_super:
 	if (err)
 		st->ss->free_super(st);
- free_name:
-	if (err)
-		free(st->devname);
  free_sysfs:
 	sysfs_free(mdi);
  close_fd:
@@ -1598,16 +1674,14 @@ unsigned long long min_recovery_start(struct mdinfo *array)
 	return recovery_start;
 }
 
-int mdmon_pid(int devnum)
+int mdmon_pid(char *devnm)
 {
 	char path[100];
 	char pid[10];
 	int fd;
 	int n;
-	char *devname = devnum2devname(devnum);
 
-	sprintf(path, "%s/%s.pid", MDMON_DIR, devname);
-	free(devname);
+	sprintf(path, "%s/%s.pid", MDMON_DIR, devnm);
 
 	fd = open(path, O_RDONLY | O_NOATIME, 0);
 
@@ -1620,9 +1694,9 @@ int mdmon_pid(int devnum)
 	return atoi(pid);
 }
 
-int mdmon_running(int devnum)
+int mdmon_running(char *devnm)
 {
-	int pid = mdmon_pid(devnum);
+	int pid = mdmon_pid(devnm);
 	if (pid <= 0)
 		return 0;
 	if (kill(pid, 0) == 0)
@@ -1630,7 +1704,7 @@ int mdmon_running(int devnum)
 	return 0;
 }
 
-int start_mdmon(int devnum)
+int start_mdmon(char *devnm)
 {
 	int i, skipped;
 	int len;
@@ -1672,7 +1746,7 @@ int start_mdmon(int devnum)
 				skipped = 0;
 
 		snprintf(pathbuf, sizeof(pathbuf), "mdmon@%s.service",
-			 devnum2devname(devnum));
+			 devnm);
 		status = execl("/usr/bin/systemctl", "systemctl", "start",
 			       pathbuf, NULL);
 		status = execl("/bin/systemctl", "systemctl", "start",
@@ -1701,7 +1775,7 @@ int start_mdmon(int devnum)
 		for (i = 0; paths[i]; i++)
 			if (paths[i][0]) {
 				execl(paths[i], "mdmon",
-				      devnum2devname(devnum), NULL);
+				      devnm, NULL);
 			}
 		exit(1);
 	case -1: pr_err("cannot run mdmon. "
@@ -1748,7 +1822,7 @@ int flush_metadata_updates(struct supertype *st)
 		return -1;
 	}
 
-	sfd = connect_monitor(devnum2devname(st->container_dev));
+	sfd = connect_monitor(st->container_devnm);
 	if (sfd < 0)
 		return -1;
 
@@ -1835,7 +1909,7 @@ struct mdinfo *container_choose_spares(struct supertype *st,
 				found = 1;
 			/* check if domain matches */
 			if (found && domlist) {
-				struct dev_policy *pol = devnum_policy(dev);
+				struct dev_policy *pol = devid_policy(dev);
 				if (spare_group)
 					pol_add(&pol, pol_domain,
 						spare_group, NULL);