Create a container member

From: Neil Brown <neilb@suse.de>

Create.c

@@ -537,7 +537,15 @@ int Create(struct supertype *st, char *mddev, int mdfd,
 
 	if (st->ss->external) {
 		char ver[100];
-		strcat(strcpy(ver, "external:"), st->ss->text_version);
+		if (st->ss->external == 1)
+			/* container */
+			strcat(strcpy(ver, "external:"), st->ss->text_version);
+		else {
+			/* member */
+			sprintf(ver, "external:/%s/%d",
+				devnum2devname(st->container_dev),
+				st->container_member);
+		}
 		if ((vers % 100) < 2 ||
 		    sra == NULL ||
 		    sysfs_set_str(sra, NULL, "metadata_version",

mdadm.h

@@ -397,6 +397,8 @@ struct supertype {
 	struct superswitch *ss;
 	int minor_version;
 	int max_devs;
+	int container_dev;    /* devnum of container */
+	int container_member; /* numerical position in container */
 	void *sb;
 	void *info;
 };
@@ -563,6 +565,8 @@ extern int open_mddev_devnum(char *devname, int devnum, char *name,
 			     char *chosen_name, int parts);
 extern int open_container(int fd);
 
+extern char *devnum2devname(int num);
+extern int fd2devnum(int fd);
 
 #define	LEVEL_MULTIPATH		(-4)
 #define	LEVEL_LINEAR		(-1)

super-ddf.c

@@ -416,7 +416,7 @@ struct ddf_super {
 #define offsetof(t,f) ((size_t)&(((t*)0)->f))
 #endif
 
-struct superswitch super_ddf_container, super_ddf_bvd;
+extern struct superswitch super_ddf_container, super_ddf_bvd;
 
 static int calc_crc(void *buf, int len)
 {
@@ -1657,6 +1657,7 @@ static int init_super_ddf_bvd(struct supertype *st,
 		return 0;
 	}
 	ve = &ddf->virt->entries[venum];
+	st->container_member = venum;
 
 	/* A Virtual Disk GUID contains the T10 Vendor ID, controller type,
 	 * timestamp, random number
@@ -2023,6 +2024,8 @@ int validate_geometry_ddf(struct supertype *st,
 		st->ss = &super_ddf_bvd;
 		if (load_super_ddf_all(st, cfd, (void **)&ddf, NULL, 1) == 0) {
 			st->sb = ddf;
+			st->container_dev = fd2devnum(cfd);
+			st->container_member = 27; // FIXME
 			close(cfd);
 			return st->ss->validate_geometry(st, level, layout,
 							 raiddisks, chunk, size,

sysfs.c

@@ -34,7 +34,7 @@ int load_sys(char *path, char *buf)
 		return -1;
 	n = read(fd, buf, 1024);
 	close(fd);
-	if (n <=0 || n >= 1024)
+	if (n <0 || n >= 1024)
 		return -1;
 	buf[n] = 0;
 	if (buf[n-1] == '\n')
@@ -316,6 +316,7 @@ int sysfs_set_array(struct mdinfo *sra,
 {
 	int rv = 0;
 	sra->array = info->array;
+
 	if (info->array.level < 0)
 		return 0; /* FIXME */
 	rv |= sysfs_set_str(sra, NULL, "level",

util.c

@@ -978,6 +978,29 @@ int open_container(int fd)
 	return -1;
 }
 
+char *devnum2devname(int num)
+{
+	char name[100];
+	if (num > 0)
+		sprintf(name, "md%d", num);
+	else
+		sprintf(name, "md_d%d", -1-num);
+	return strdup(name);
+}
+
+int fd2devnum(int fd)
+{
+	struct stat stb;
+	if (fstat(fd, &stb) == 0 &&
+	    (S_IFMT&stb.st_mode)==S_IFBLK) {
+		if (major(stb.st_rdev) == MD_MAJOR)
+			return minor(stb.st_rdev);
+		else
+			return -1- (minor(stb.st_rdev)>>6);
+	}
+	return -1;
+}
+
 #ifdef __TINYC__
 /* tinyc doesn't optimize this check in ioctl.h out ... */
 unsigned int __invalid_size_argument_for_IOC = 0;