From: NeilBrown <neilb@suse.de>
Date: Thu, 18 Sep 2008 06:21:08 +0000 (+1000)
Subject: Add support for assembling specific subarrays.
X-Git-Tag: mdadm-3.0-devel1~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dbb44303d7d3ad8fffb9e25c8ed6fd57afa57b95;p=thirdparty%2Fmdadm.git

Add support for assembling specific subarrays.

This normally isn't needed as --incremental does all the work.
But it is needed to recognise member= and container= in mdadm.conf
---

diff --git a/Incremental.c b/Incremental.c
index 6474e796..6223113c 100644
--- a/Incremental.c
+++ b/Incremental.c
@@ -793,6 +793,7 @@ int Incremental_container(struct supertype *st, char *devname, int verbose,
 		struct map_ent *mp, *map = NULL;
 		char nbuf[64];
 		char *name_to_use;
+		struct mddev_ident_s *match = NULL;
 
 		if ((autof&7) == 3 || (autof&7) == 5)
 			usepart = 0;
@@ -806,10 +807,51 @@ int Incremental_container(struct supertype *st, char *devname, int verbose,
 			)
 			name_to_use = fname_from_uuid(st, ra, nbuf, '-');
 		    
-		if (mp)
+		if (!mp) {
+
+			/* Check in mdadm.conf for devices == devname and
+			 * member == ra->text_version after second slash.
+			 */
+			char *sub = strchr(ra->text_version+1, '/');
+			struct mddev_ident_s *array_list;
+			if (sub) {
+				sub++;
+				array_list = conf_get_ident(NULL);
+			} else
+				array_list = NULL;
+			for(; array_list ; array_list = array_list->next) {
+				int fd;
+				char *dn;
+				if (array_list->member == NULL ||
+				    array_list->container == NULL)
+					continue;
+				if (strcmp(array_list->member, sub) != 0)
+					continue;
+				fd = open(array_list->container, O_RDONLY);
+				if (fd < 0)
+					continue;
+				dn = devnum2devname(fd2devnum(fd));
+				close(fd);
+				if (strncmp(dn, ra->text_version+1,
+					    strlen(dn)) != 0 ||
+				    ra->text_version[strlen(dn)+1] != '/') {
+					free(dn);
+					continue;
+				}
+				free(dn);
+				/* we have a match */
+				match = array_list;
+				break;
+			}
+		}
+
+		if (match && is_standard(match->devname, &devnum))
+			/* we have devnum now */;
+		else if (mp)
 			devnum = mp->devnum;
+		else if (is_standard(name_to_use, &devnum))
+			/* have devnum */;
 		else {
-
 			n = name_to_use;
 			if (*n == 'd')
 				n++;
@@ -851,7 +893,8 @@ int Incremental_container(struct supertype *st, char *devname, int verbose,
 			else
 				devnum = find_free_devnum(usepart);
 		}
-		mdfd = open_mddev_devnum(mp ? mp->path : NULL, devnum, name_to_use,
+		mdfd = open_mddev_devnum(mp ? mp->path : match ? match->devname : NULL,
+					 devnum, name_to_use,
 					 chosen_name, autof>>3);
 
 		if (mdfd < 0) {
diff --git a/config.c b/config.c
index 121b3373..f471cf36 100644
--- a/config.c
+++ b/config.c
@@ -516,6 +516,12 @@ void arrayline(char *line)
 		} else if (strncasecmp(w, "auto=", 5) == 0 ) {
 			/* whether to create device special files as needed */
 			mis.autof = parse_auto(w+5, "auto type", 0);
+		} else if (strncasecmp(w, "member=", 7) == 0) {
+			/* subarray within a container */
+			mis.member = strdup(w+7);
+		} else if (strncasecmp(w, "container=", 10) == 0) {
+			/* the container holding this subarray */
+			mis.container = strdup(w+10);
 		} else {
 			fprintf(stderr, Name ": unrecognised word on ARRAY line: %s\n",
 				w);
diff --git a/mdadm.h b/mdadm.h
index f3270207..8b6baa61 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -259,6 +259,12 @@ typedef struct mddev_ident_s {
 	char	*bitmap_file;
 	int	bitmap_fd;
 
+	char	*container;	/* /dev/whatever name of container.  You
+				 * would expect this to be the 'devname'
+				 * of some other entry.
+				 */
+	char	*member;	/* subarray within a container */
+
 	struct mddev_ident_s *next;
 } *mddev_ident_t;