Create: cleanup/unify default geometry handling

Support metadata specific level, layout and chunksize defaults.  Kill an
uneeded superswitch methods ahead of adding more for the reshape case.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

Create.c

@@ -31,8 +31,8 @@ static int default_layout(struct supertype *st, int level, int verbose)
 {
 	int layout = UnSet;
 
-	if (st && st->ss->default_layout)
+	if (st && st->ss->default_geometry)
-		layout = st->ss->default_layout(level);
+		st->ss->default_geometry(st, &level, &layout, NULL);
 
 	if (layout == UnSet)
 		switch(level) {
@@ -120,15 +120,8 @@ int Create(struct supertype *st, char *mddev,
 	int major_num = BITMAP_MAJOR_HI;
 
 	memset(&info, 0, sizeof(info));
-
+	if (level == UnSet && st && st->ss->default_geometry)
-	if (level == UnSet) {
+		st->ss->default_geometry(st, &level, NULL, NULL);
-		/* "ddf" and "imsm" metadata only supports one level - should possibly
-		 * push this into metadata handler??
-		 */
-		if (st && (st->ss == &super_ddf || st->ss == &super_imsm))
-			level = LEVEL_CONTAINER;
-	}
-
 	if (level == UnSet) {
 		fprintf(stderr,
 			Name ": a RAID level is needed to create an array.\n");
@@ -235,11 +228,9 @@ int Create(struct supertype *st, char *mddev,
 	case 6:
 	case 0:
 		if (chunk == 0) {
-			if (st && st->ss->default_chunk)
+			if (st && st->ss->default_geometry)
-				chunk = st->ss->default_chunk(st);
+				st->ss->default_geometry(st, NULL, NULL, &chunk);
-
 			chunk = chunk ? : 512;
-
 			if (verbose > 0)
 				fprintf(stderr, Name ": chunk size defaults to %dK\n", chunk);
 		}

mdadm.h

@@ -626,7 +626,7 @@ extern struct superswitch {
 	 * added to validate changing size and new devices.  If there are
 	 * inter-device dependencies, it should record sufficient details
 	 * so these can be validated.
-	 * Both 'size' and '*freesize' are in sectors.  chunk is bytes.
+	 * Both 'size' and '*freesize' are in sectors.  chunk is KiB.
 	 */
 	int (*validate_geometry)(struct supertype *st, int level, int layout,
 				 int raiddisks,
@@ -635,10 +635,8 @@ extern struct superswitch {
 				 int verbose);
 
 	struct mdinfo *(*container_content)(struct supertype *st, char *subarray);
-	/* Allow a metadata handler to override mdadm's default layouts */
+	/* query the supertype for default geometry */
-	int (*default_layout)(int level); /* optional */
+	void (*default_geometry)(struct supertype *st, int *level, int *layout, int *chunk); /* optional */
-	/* query the supertype for default chunk size */
-	int (*default_chunk)(struct supertype *st); /* optional */
 	/* Permit subarray's to be deleted from inactive containers */
 	int (*kill_subarray)(struct supertype *st); /* optional */
 	/* Permit subarray's to be modified */

super-ddf.c

@@ -3643,6 +3643,15 @@ static int ddf_level_to_layout(int level)
 	}
 }
 
+static void default_geometry_ddf(struct supertype *st, int *level, int *layout, int *chunk)
+{
+	if (level && *level == UnSet)
+		*level = LEVEL_CONTAINER;
+
+	if (level && layout && *layout == UnSet)
+		*layout = ddf_level_to_layout(*level);
+}
+
 struct superswitch super_ddf = {
 #ifndef	MDASSEMBLE
 	.examine_super	= examine_super_ddf,
@@ -3671,7 +3680,7 @@ struct superswitch super_ddf = {
 	.free_super	= free_super_ddf,
 	.match_metadata_desc = match_metadata_desc_ddf,
 	.container_content = container_content_ddf,
-	.default_layout	= ddf_level_to_layout,
+	.default_geometry = default_geometry_ddf,
 
 	.external	= 1,
 

super-intel.c

@@ -4180,14 +4180,18 @@ static int validate_geometry_imsm(struct supertype *st, int level, int layout,
 	return 0;
 }
 
-static int default_chunk_imsm(struct supertype *st)
+static void default_geometry_imsm(struct supertype *st, int *level, int *layout, int *chunk)
 {
 	struct intel_super *super = st->sb;
 
-	if (!super->orom)
+	if (level && *level == UnSet)
-		return 0;
+		*level = LEVEL_CONTAINER;
 
-	return imsm_orom_default_chunk(super->orom);
+	if (level && layout && *layout == UnSet)
+		*layout = imsm_level_to_layout(*level);
+
+	if (chunk && (*chunk == UnSet || *chunk == 0) && super->orom)
+		*chunk = imsm_orom_default_chunk(super->orom);
 }
 
 static void handle_missing(struct intel_super *super, struct imsm_dev *dev);
@@ -5680,7 +5684,6 @@ struct superswitch super_imsm = {
 	.brief_detail_super = brief_detail_super_imsm,
 	.write_init_super = write_init_super_imsm,
 	.validate_geometry = validate_geometry_imsm,
-	.default_chunk	= default_chunk_imsm,
 	.add_to_super	= add_to_super_imsm,
 	.detail_platform = detail_platform_imsm,
 	.kill_subarray = kill_subarray_imsm,
@@ -5704,7 +5707,7 @@ struct superswitch super_imsm = {
 	.free_super	= free_super_imsm,
 	.match_metadata_desc = match_metadata_desc_imsm,
 	.container_content = container_content_imsm,
-	.default_layout = imsm_level_to_layout,
+	.default_geometry = default_geometry_imsm,
 	.get_disk_controller_domain = imsm_get_disk_controller_domain,
 
 	.external	= 1,