When assembling with --auto, honour common device names

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>

5 files changed, 106 insertions, 62 deletions

diff --git a/ChangeLog b/ChangeLog
index d282f494..092be389 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,11 @@ Changes Prior to 1.9.0 release
     -   Fix rpm build problem (stray %)
     -   Minor manpage updates
     -   Change "dirty" status to "active" as it was confusing people.
+    -   --assemble --auto recognises 'standard' name and insists on using
+        the appropriate major/minor number for them.
+    -   Remove underscore from partition names, so partitions of 
+	"foo" are "foo1", "foo2" etc (unchanged) and partitions of
+	"f00" are "f00p1", "f00p2" etc rather than "f00_p1"...
 
 Changes Prior to 1.8.0 release
     -   Makefile cleanup from  Luca Berra <bluca@comedia.it>
diff --git a/mdadm.c b/mdadm.c
index ee4f14b8..1c67b3b9 100644
--- a/mdadm.c
+++ b/mdadm.c
@@ -66,7 +66,14 @@ int main(int argc, char *argv[])
 	int force = 0;
 	int test = 0;
 	int assume_clean = 0;
-	int autof = 0; /* -1 for non-partitions, 1 or more to create partitions */
+	int autof = 0; /* -2 means create device based on name:
+			*    if it ends mdN, then non-partitioned array N
+			*    if it ends dN, then partitions array N
+			* -1 means create non-partitioned, choose N
+			*  1 or more to create partitioned
+			* If -1 or 1 and name is a 'standard' name, then
+			* insist on a match of type and number.
+			*/
 
 	char *mailaddr = NULL;
 	char *program = NULL;
@@ -401,10 +408,12 @@ int main(int argc, char *argv[])
 		case O(BUILD,'a'):
 		case O(ASSEMBLE,'a'): /* auto-creation of device node */
 			if (optarg == NULL)
-				autof = -1;
+				autof = -2;
 			else if (strcasecmp(optarg,"no")==0)
 				autof = 0;
-			else if (strcasecmp(optarg,"yes")==0 || strcasecmp(optarg,"md")==0)
+			else if (strcasecmp(optarg,"yes")==0)
+				autof = -2;
+			else if (strcasecmp(optarg,"md")==0)
 				autof = -1;
 			else {
 				/* There might be digits, and maybe a hypen, at the end */
diff --git a/mdadm.h b/mdadm.h
index a816846c..b7f34d10 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -200,7 +200,7 @@ extern int check_reiser(int fd, char *name);
 extern int check_raid(int fd, char *name);
 
 extern int get_mdp_major(void);
-extern int is_standard(char *dev);
+extern int is_standard(char *dev, int *nump);
 
 
 extern mddev_ident_t conf_get_ident(char *conffile, char *dev);
diff --git a/mdopen.c b/mdopen.c
index 69c4a232..4e1ce6ad 100644
--- a/mdopen.c
+++ b/mdopen.c
@@ -35,7 +35,7 @@ void make_parts(char *dev, int cnt)
 {
 	/* make 'cnt' partition devices for 'dev'
 	 * We use the major/minor from dev and add 1..cnt
-	 * If dev ends with a digit, we add "_p%d" else "%d"
+	 * If dev ends with a digit, we add "p%d" else "%d"
 	 * If the name exists, we use it's owner/mode,
 	 * else that of dev
 	 */
@@ -53,7 +53,7 @@ void make_parts(char *dev, int cnt)
 	minor = MINOR(stb.st_rdev);
 	for (i=1; i <= cnt ; i++) {
 		struct stat stb2;
-		sprintf(name, "%s%s%d", dev, dig?"_p":"", i);
+		sprintf(name, "%s%s%d", dev, dig?"p":"", i);
 		if (stat(name, &stb2)==0) {
 			if (!S_ISBLK(stb2.st_mode))
 				continue;
@@ -75,7 +75,7 @@ void make_parts(char *dev, int cnt)
  * If the name already exists, and is not a block device, we fail.
  * If it exists and is not an md device, is not the right type (partitioned or not),
  * or is currently in-use, we remove the device, but remember the owner and mode.
- * If it now doesn't exist, we find a few md array and create the device.
+ * If it now doesn't exist, we find a new md array and create the device.
  * Default ownership is user=0, group=0 perm=0600
  */
 int open_mddev(char *dev, int autof)
@@ -128,55 +128,76 @@ int open_mddev(char *dev, int autof)
 			}
 		}
 		/* Ok, need to find a minor that is not in use.
-		 * Easiest to read /proc/mdstat, and hunt through for
+		 * If the device name is in a 'standard' format,
+		 * intuit the minor from that, else
+		 * easiest to read /proc/mdstat, and hunt through for
 		 * an unused number 
 		 */
-		mdlist = mdstat_read(0);
-		for (num= (autof>0)?-1:0 ; ; num+= (autof>2)?-1:1) {
-			struct mdstat_ent *me;
-			for (me=mdlist; me; me=me->next)
-				if (me->devnum == num)
-					break;
-			if (!me) {
-				/* doesn't exist if mdstat.
-				 * make sure it is new to /dev too
-				 */
-				char *dn;
-				if (autof > 0) 
-					minor = (-1-num) << MdpMinorShift;
-				else
-					minor = num;
-				dn = map_dev(major,minor);
-				if (dn==NULL || is_standard(dn)) {
-					/* this number only used by a 'standard' name,
-					 * so it is safe to use
+		switch(is_standard(dev, &num)) {
+		case -1: /* non partitioned */
+			if (autof > 0) {
+				fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
+				return -1;
+			}
+			minor = num;
+			num = -1-num;
+			break;
+		case 1: /* partitioned */
+			if (autof == -1) {
+				fprintf(stderr, Name ": that --auto option not compatable with device named %s\n", dev);
+				return -1;
+			}
+			minor = num <<  MdpMinorShift;
+			major = get_mdp_major();
+			break;
+		case 0: /* not standard, pick an unused number */
+			mdlist = mdstat_read(0);
+			for (num= (autof>0)?-1:0 ; ; num+= (autof>2)?-1:1) {
+				struct mdstat_ent *me;
+				for (me=mdlist; me; me=me->next)
+					if (me->devnum == num)
+						break;
+				if (!me) {
+					/* doesn't exist if mdstat.
+					 * make sure it is new to /dev too
 					 */
-					break;
+					char *dn;
+					if (autof > 0) 
+						minor = (-1-num) << MdpMinorShift;
+					else
+						minor = num;
+					dn = map_dev(major,minor);
+					if (dn==NULL || is_standard(dn, NULL)) {
+						/* this number only used by a 'standard' name,
+						 * so it is safe to use
+						 */
+						break;
+					}
 				}
 			}
 		}
-		/* 'num' is the number to use, >=0 for md, <0 for mdp */
-		if (must_remove) {
-			/* never remove a device name that ends /mdNN or /dNN,
-			 * that would be confusing 
-			 */
-			if (is_standard(dev)) {
-				fprintf(stderr, Name ": --auto refusing to remove %s as it looks like a standard name.\n",
-					dev);
+		/* major and minor have been chosen */
+		
+		/* If it was a 'standard' name and it is in-use, then
+		 * the device could already be correct
+		 */
+		if (stb.st_mode && MAJOR(stb.st_rdev) == major &&
+		    MINOR(stb.st_rdev) == minor)
+			;
+		else {
+			if (must_remove)
+				unlink(dev);
+
+			if (mknod(dev, S_IFBLK|0600, MKDEV(major, minor))!= 0) {
+				fprintf(stderr, Name ": failed to create %s\n", dev);
 				return -1;
 			}
-			unlink(dev);
-		}
-
-		if (mknod(dev, S_IFBLK|0600, MKDEV(major, minor))!= 0) {
-			fprintf(stderr, Name ": failed to create %s\n", dev);
-			return -1;
-		}
-		if (must_remove) {
-			chown(dev, stb.st_uid, stb.st_gid);
-			chmod(dev, stb.st_mode & 07777);
+			if (must_remove) {
+				chown(dev, stb.st_uid, stb.st_gid);
+				chmod(dev, stb.st_mode & 07777);
+			}
+			make_parts(dev,autof);
 		}
-		make_parts(dev,autof);
 	}
 	mdfd = open(dev, O_RDWR, 0);
 	if (mdfd < 0)
diff --git a/util.c b/util.c
index 121ddbb7..23968714 100644
--- a/util.c
+++ b/util.c
@@ -395,28 +395,37 @@ int map_name(mapping_t *map, char *name)
 }
 
 
-int is_standard(char *dev)
+int is_standard(char *dev, int *nump)
 {
 	/* tests if dev is a "standard" md dev name.
 	 * i.e if the last component is "/dNN" or "/mdNN",
 	 * where NN is a string of digits 
 	 */
-	dev = strrchr(dev, '/');
-	if (!dev)
+	char *d = strrchr(dev, '/');
+	int type=0;
+	int num;
+	if (!d)
 		return 0;
-	if (strncmp(dev, "/d",2)==0)
-		dev += 2;
-	else if (strncmp(dev, "/md", 3)==0)
-		dev += 3;
+	if (strncmp(d, "/d",2)==0)
+		d += 2, type=1; /* /dev/md/dN{pM} */
+	else if (strncmp(d, "/md_d", 5)==0)
+		d += 5, type=1; /* /dev/md_dNpM */
+	else if (strncmp(d, "/md", 3)==0)
+		d += 3, type=-1; /* /dev/mdN */
+	else if (d-dev > 3 && strncmp(d-2, "md/", 3)==0)
+		type = -1; /* /dev/md/N */
 	else
 		return 0;
-	if (!*dev)
+	if (!*d)
 		return 0;
-	while (isdigit(*dev))
-		dev++;
-	if (*dev)
+	num = atoi(d);
+	while (isdigit(*d))
+		d++;
+	if (*d)
 		return 0;
-	return 1;
+	if (nump) *nump = num;
+
+	return type;
 }
 
 
@@ -468,7 +477,7 @@ int add_dev(const char *name, const struct stat *stb, int flag)
 
 /*
  * Find a block device with the right major/minor number.
- * Avoid /dev/mdNN and /dev/md/dNN is possible
+ * Avoid /dev/mdNN and /dev/md/dNN if possible
  */
 char *map_dev(int major, int minor)
 {
@@ -486,7 +495,7 @@ char *map_dev(int major, int minor)
 	for (p=devlist; p; p=p->next)
 		if (p->major == major &&
 		    p->minor == minor) {
-			if (is_standard(p->name))
+			if (is_standard(p->name, NULL))
 				std = p->name;
 			else
 				return p->name;
@@ -620,7 +629,7 @@ char *get_md_name(int dev)
 		    && (stb.st_rdev == rdev))
 			return devname;
 	}
-	dn = map_dev(MAJOR(rdev), MINOR(rdev));
+	dn = map_dev(major(rdev), minor(rdev));
 	if (dn)
 		return dn;
 	sprintf(devname, "/dev/.tmp.md%d", dev);