Add subarray arg to container_content.

This allows the info for a single array to be extracted,
so we don't have to write it into st->subarray.

For consistency, implement container_content for super0 and super1,
to just return the mdinfo for the single array.

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

Assemble.c

@@ -331,7 +331,7 @@ int Assemble(struct supertype *st, char *mddev,
 			if (tmpdev->content)
 				content = tmpdev->content;
 			else
-				content = tst->ss->container_content(tst);
+				content = tst->ss->container_content(tst, NULL);
 			if (!content)
 				goto loop; /* empty container */
 

Incremental.c

@@ -1190,7 +1190,7 @@ int Incremental_container(struct supertype *st, char *devname, int verbose,
 	 * array, choose a device name and assemble the array.
 	 */
 
-	struct mdinfo *list = st->ss->container_content(st);
+	struct mdinfo *list = st->ss->container_content(st, NULL);
 	struct mdinfo *ra;
 	struct map_ent *map = NULL;
 

mdadm.h

@@ -621,7 +621,7 @@ extern struct superswitch {
 				 char *subdev, unsigned long long *freesize,
 				 int verbose);
 
-	struct mdinfo *(*container_content)(struct supertype *st);
+	struct mdinfo *(*container_content)(struct supertype *st, char *subarray);
 	/* Allow a metadata handler to override mdadm's default layouts */
 	int (*default_layout)(int level); /* optional */
 	/* query the supertype for default chunk size */

super-ddf.c

@@ -2924,7 +2924,7 @@ static int load_super_ddf_all(struct supertype *st, int fd,
 }
 #endif /* MDASSEMBLE */
 
-static struct mdinfo *container_content_ddf(struct supertype *st)
+static struct mdinfo *container_content_ddf(struct supertype *st, char *subarray)
 {
 	/* Given a container loaded by load_super_ddf_all,
 	 * extract information about all the arrays into
@@ -2943,6 +2943,13 @@ static struct mdinfo *container_content_ddf(struct supertype *st)
 		unsigned int i;
 		unsigned int j;
 		struct mdinfo *this;
+		char *ep;
+
+		if (subarray &&
+		    (strtoul(subarray, &ep, 10) != vc->vcnum ||
+		     *ep != '\0'))
+			continue;
+
 		this = malloc(sizeof(*this));
 		memset(this, 0, sizeof(*this));
 		this->next = rest;

super-intel.c

@@ -4327,11 +4327,12 @@ static void update_recovery_start(struct imsm_dev *dev, struct mdinfo *array)
 }
 
 
-static struct mdinfo *container_content_imsm(struct supertype *st)
+static struct mdinfo *container_content_imsm(struct supertype *st, char *subarray)
 {
 	/* Given a container loaded by load_super_imsm_all,
 	 * extract information about all the arrays into
 	 * an mdinfo tree.
+	 * If 'subarray' is given, just extract info about that array.
 	 *
 	 * For each imsm_dev create an mdinfo, fill it in,
 	 *  then look for matching devices in super->disks
@@ -4340,7 +4341,7 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
 	struct intel_super *super = st->sb;
 	struct imsm_super *mpb = super->anchor;
 	struct mdinfo *rest = NULL;
-	int i;
+	unsigned int i;
 
 	/* do not assemble arrays that might have bad blocks */
 	if (imsm_bbm_log_size(super->anchor)) {
@@ -4350,10 +4351,18 @@ static struct mdinfo *container_content_imsm(struct supertype *st)
 	}
 
 	for (i = 0; i < mpb->num_raid_devs; i++) {
-		struct imsm_dev *dev = get_imsm_dev(super, i);
-		struct imsm_map *map = get_imsm_map(dev, 0);
+		struct imsm_dev *dev;
+		struct imsm_map *map;
 		struct mdinfo *this;
 		int slot;
+		char *ep;
+
+		if (subarray &&
+		    (i != strtoul(subarray, &ep, 10) || *ep != '\0'))
+			continue;
+
+		dev = get_imsm_dev(super, i);
+		map = get_imsm_map(dev, 0);
 
 		/* do not publish arrays that are in the middle of an
 		 * unsupported migration

super0.c

@@ -401,6 +401,17 @@ static void getinfo_super0(struct supertype *st, struct mdinfo *info, char *map)
 	info->array.working_disks = working;
 }
 
+static struct mdinfo *container_content0(struct supertype *st, char *subarray)
+{
+	struct mdinfo *info;
+
+	if (subarray)
+		return NULL;
+
+	info = malloc(sizeof(*info));
+	getinfo_super0(st, info, NULL);
+	return info;
+}
 
 static int update_super0(struct supertype *st, struct mdinfo *info,
 			 char *update,
@@ -1136,6 +1147,7 @@ struct superswitch super0 = {
 	.match_home = match_home0,
 	.uuid_from_super = uuid_from_super0,
 	.getinfo_super = getinfo_super0,
+	.container_content = container_content0,
 	.update_super = update_super0,
 	.init_super = init_super0,
 	.store_super = store_super0,

super1.c

@@ -645,6 +645,18 @@ static void getinfo_super1(struct supertype *st, struct mdinfo *info, char *map)
 	info->array.working_disks = working;
 }
 
+static struct mdinfo *container_content1(struct supertype *st, char *subarray)
+{
+	struct mdinfo *info;
+
+	if (subarray)
+		return NULL;
+
+	info = malloc(sizeof(*info));
+	getinfo_super1(st, info, NULL);
+	return info;
+}
+
 static int update_super1(struct supertype *st, struct mdinfo *info,
 			 char *update,
 			 char *devname, int verbose,
@@ -1683,6 +1695,7 @@ struct superswitch super1 = {
 	.match_home = match_home1,
 	.uuid_from_super = uuid_from_super1,
 	.getinfo_super = getinfo_super1,
+	.container_content = container_content1,
 	.update_super = update_super1,
 	.init_super = init_super1,
 	.store_super = store_super1,