Assemble: allow members of containers to be assembled and auto-assembled.

Try to treat members of containers much like other arrays for
assembly.
We still look through the list of devices for a match (it will be
the container), then find the relevant 'info' and try to assemble
the array.

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

Assemble.c

@@ -50,7 +50,7 @@ static int name_matches(char *found, char *required, char *homehost)
 	return 0;
 }
 
-/*static */ int is_member_busy(char *metadata_version)
+static int is_member_busy(char *metadata_version)
 {
 	/* check if the given member array is active */
 	struct mdstat_ent *mdstat = mdstat_read(1, 0);
@@ -273,6 +273,62 @@ int Assemble(struct supertype *st, char *mddev,
 		}
 		if (dfd >= 0) close(dfd);
 
+		if (tst && tst->sb && tst->ss->container_content
+		    && tst->loaded_container) {
+			/* tmpdev is a container.  We need to be either
+			 * looking for a member, or auto-assembling
+			 */
+			if (st) {
+				/* already found some components, this cannot
+				 * be another one.
+				 */
+				if (report_missmatch)
+					fprintf(stderr, Name ": %s is a container, but we are looking for components\n",
+						devname);
+				goto loop;
+			}
+
+			if (ident->container) {
+				if (ident->container[0] == '/' &&
+				    !same_dev(ident->container, devname)) {
+					if (report_missmatch)
+						fprintf(stderr, Name ": %s is not the container required (%s)\n",
+							devname, ident->container);
+					goto loop;
+				}
+				if (ident->container[0] != '/') {
+					/* we have a uuid */
+					int uuid[4];
+					if (!parse_uuid(ident->container, uuid) ||
+					    !same_uuid(content->uuid, uuid, tst->ss->swapuuid)) {
+						if (report_missmatch)
+							fprintf(stderr, Name ": %s has wrong UUID to be required container\n",
+								devname);
+						goto loop;
+					}
+				}
+			}
+			/* It is worth looking inside this container.
+			 */
+		next_member:
+			if (tmpdev->content)
+				content = tmpdev->content;
+			else
+				content = tst->ss->container_content(tst);
+
+			tmpdev->content = content->next;
+			if (tmpdev->content == NULL)
+				tmpdev->used = 1;
+
+		} else if (ident->container || ident->member) {
+			/* No chance of this matching if we don't have
+			 * a container */
+			if (report_missmatch)
+				fprintf(stderr, Name "%s is not a container, and one is required.\n",
+					devname);
+			goto loop;
+		}
+
 		if (ident->uuid_set && (!update || strcmp(update, "uuid")!= 0) &&
 		    (!tst || !tst->sb ||
 		     same_uuid(content->uuid, ident->uuid, tst->ss->swapuuid)==0)) {
@@ -332,6 +388,30 @@ int Assemble(struct supertype *st, char *mddev,
 			return 1;
 		}
 
+		if (tst && tst->sb && tst->ss->container_content
+		    && tst->loaded_container) {
+			/* we have the one container we need, don't keep
+			 * looking.  If the chosen member is active, skip.
+			 */
+			if (is_member_busy(content->text_version)) {
+				if (auto_assem)
+					goto loop;
+				fprintf(stderr, Name ": member %s in %s is already assembled\n",
+					content->text_version,
+					devname);
+				tst->ss->free_super(tst);
+				return 1;
+			}
+			st = tst; tst = NULL;
+			if (!auto_assem && tmpdev->next != NULL) {
+				fprintf(stderr, Name ": %s is a container, but is not "
+					"only device given: confused and aborting\n",
+					devname);
+				st->ss->free_super(st);
+				return 1;
+			}
+			break;
+		}
 		if (st == NULL)
 			st = dup_super(tst);
 		if (st->minor_version == -1)
@@ -380,6 +460,8 @@ int Assemble(struct supertype *st, char *mddev,
 		tmpdev->used = 1;
 
 	loop:
+		if (tmpdev->content)
+			goto next_member;
 		if (tst)
 			tst->ss->free_super(tst);
 	}
@@ -458,6 +540,13 @@ int Assemble(struct supertype *st, char *mddev,
 	}
 	ioctl(mdfd, STOP_ARRAY, NULL); /* just incase it was started but has no content */
 
+#ifndef MDASSEMBLE
+	if (content != &info) {
+		/* This is a member of a container.  Try starting the array. */
+		return assemble_container_content(st, mdfd, content, runstop,
+					   chosen_name, verbose);
+	}
+#endif
 	/* Ok, no bad inconsistancy, we can try updating etc */
 	bitmap_done = 0;
 	for (tmpdev = devlist; tmpdev; tmpdev=tmpdev->next) if (tmpdev->used == 1) {

config.c

@@ -261,6 +261,7 @@ mddev_dev_t load_partitions(void)
 		d->devname = strdup(name);
 		d->next = rv;
 		d->used = 0;
+		d->content = NULL;
 		rv = d;
 	}
 	fclose(f);
@@ -290,6 +291,7 @@ mddev_dev_t load_containers(void)
 			}
 			d->next = rv;
 			d->used = 0;
+			d->content = NULL;
 			rv = d;
 		}
 	free_mdstat(mdstat);
@@ -803,6 +805,7 @@ mddev_dev_t conf_get_devs()
 			t->devname = strdup(globbuf.gl_pathv[i]);
 			t->next = dlist;
 			t->used = 0;
+			t->content = NULL;
 			dlist = t;
 /*	printf("one dev is %s\n", t->devname);*/
 		}

mdadm.c

@@ -256,6 +256,7 @@ int main(int argc, char *argv[])
 					dv->writemostly = writemostly;
 					dv->re_add = re_add;
 					dv->used = 0;
+					dv->content = NULL;
 					dv->next = NULL;
 					*devlistend = dv;
 					devlistend = &dv->next;
@@ -308,6 +309,8 @@ int main(int argc, char *argv[])
 			dv->disposition = devmode;
 			dv->writemostly = writemostly;
 			dv->re_add = re_add;
+			dv->used = 0;
+			dv->content = NULL;
 			dv->next = NULL;
 			*devlistend = dv;
 			devlistend = &dv->next;

mdadm.h

@@ -278,6 +278,8 @@ typedef struct mddev_dev_s {
 	char writemostly;	/* 1 for 'set writemostly', 2 for 'clear writemostly' */
 	char re_add;
 	char used;		/* set when used */
+	struct mdinfo *content;	/* If devname is a container, this might list
+				 * the remaining member arrays. */
 	struct mddev_dev_s *next;
 } *mddev_dev_t;
 
@@ -758,6 +760,7 @@ extern int get_mdp_major(void);
 extern int dev_open(char *dev, int flags);
 extern int open_dev_excl(int devnum);
 extern int is_standard(char *dev, int *nump);
+extern int same_dev(char *one, char *two);
 
 extern int parse_auto(char *str, char *msg, int config);
 extern mddev_ident_t conf_get_ident(char *dev);

util.c

@@ -828,6 +828,20 @@ int open_dev_excl(int devnum)
 	return -1;
 }
 
+int same_dev(char *one, char *two)
+{
+	struct stat st1, st2;
+	if (stat(one, &st1) != 0)
+		return 0;
+	if (stat(two, &st2) != 0)
+		return 0;
+	if ((st1.st_mode & S_IFMT) != S_IFBLK)
+		return 0;
+	if ((st2.st_mode & S_IFMT) != S_IFBLK)
+		return 0;
+	return st1.st_rdev == st2.st_rdev;
+}
+
 struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
 
 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)