From a18a888ea7944aa1718e7a0daccb6f0a13b2e34d Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@intel.com>
Date: Tue, 20 Jan 2009 01:36:50 -0700
Subject: Create: allow per-metadata default layouts

Let handlers specifiy their own defaults, specifically needed for the
imsm-raid5 case where mdadm defaults to 'ls' and imsm to 'la'.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 Create.c      | 73 +++++++++++++++++++++++++++++++++++++++--------------------
 mdadm.h       |  2 ++
 super-intel.c |  3 ++-
 3 files changed, 52 insertions(+), 26 deletions(-)

diff --git a/Create.c b/Create.c
index 422b46d..a7275d3 100644
--- a/Create.c
+++ b/Create.c
@@ -32,6 +32,44 @@
 #include	"md_p.h"
 #include	<ctype.h>
 
+static int default_layout(struct supertype *st, int level, int verbose)
+{
+	int layout = UnSet;
+
+	if (st && st->ss->default_layout)
+		layout = st->ss->default_layout(level);
+
+	if (layout == UnSet)
+		switch(level) {
+		default: /* no layout */
+			layout = 0;
+			break;
+		case 10:
+			layout = 0x102; /* near=2, far=1 */
+			if (verbose > 0)
+				fprintf(stderr,
+					Name ": layout defaults to n1\n");
+			break;
+		case 5:
+		case 6:
+			layout = map_name(r5layout, "default");
+			if (verbose > 0)
+				fprintf(stderr,
+					Name ": layout defaults to %s\n", map_num(r5layout, layout));
+			break;
+		case LEVEL_FAULTY:
+			layout = map_name(faultylayout, "default");
+
+			if (verbose > 0)
+				fprintf(stderr,
+					Name ": layout defaults to %s\n", map_num(faultylayout, layout));
+			break;
+		}
+
+	return layout;
+}
+
+
 int Create(struct supertype *st, char *mddev,
 	   int chunk, int level, int layout, unsigned long long size, int raiddisks, int sparedisks,
 	   char *name, char *homehost, int *uuid,
@@ -78,6 +116,7 @@ int Create(struct supertype *st, char *mddev,
 	unsigned long long bitmapsize;
 	struct mdinfo info, *infos;
 	int did_default = 0;
+	int do_default_layout = 0;
 	unsigned long safe_mode_delay = 0;
 	char chosen_name[1024];
 	struct map_ent *map = NULL;
@@ -175,32 +214,12 @@ int Create(struct supertype *st, char *mddev,
 	}
 
 	/* now set some defaults */
-	if (layout == UnSet)
-		switch(level) {
-		default: /* no layout */
-			layout = 0;
-			break;
-		case 10:
-			layout = 0x102; /* near=2, far=1 */
-			if (verbose > 0)
-				fprintf(stderr,
-					Name ": layout defaults to n1\n");
-			break;
-		case 5:
-		case 6:
-			layout = map_name(r5layout, "default");
-			if (verbose > 0)
-				fprintf(stderr,
-					Name ": layout defaults to %s\n", map_num(r5layout, layout));
-			break;
-		case LEVEL_FAULTY:
-			layout = map_name(faultylayout, "default");
 
-			if (verbose > 0)
-				fprintf(stderr,
-					Name ": layout defaults to %s\n", map_num(faultylayout, layout));
-			break;
-		}
+
+	if (layout == UnSet) {
+		do_default_layout = 1;
+		layout = default_layout(st, level, verbose);
+	}
 
 	if (level == 10)
 		/* check layout fits in array*/
@@ -280,6 +299,8 @@ int Create(struct supertype *st, char *mddev,
 			char *name = "default";
 			for(i=0; !st && superlist[i]; i++) {
 				st = superlist[i]->match_metadata_desc(name);
+				if (do_default_layout)
+					layout = default_layout(st, level, verbose);
 				if (st && !st->ss->validate_geometry
 					    	(st, level, layout, raiddisks,
 						 chunk, size*2, dname, &freesize,
@@ -297,6 +318,8 @@ int Create(struct supertype *st, char *mddev,
 			    st->minor_version != 90)
 				did_default = 1;
 		} else {
+			if (do_default_layout)
+				layout = default_layout(st, level, verbose);
 			if (!st->ss->validate_geometry(st, level, layout,
 						       raiddisks,
 						       chunk, size*2, dname,
diff --git a/mdadm.h b/mdadm.h
index 8220535..3ee2790 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -545,6 +545,8 @@ extern struct superswitch {
 				 int verbose);
 
 	struct mdinfo *(*container_content)(struct supertype *st);
+	/* Allow a metadata handler to override mdadm's default layouts */
+	int (*default_layout)(int level); /* optional */
 
 /* for mdmon */
 	int (*open_new)(struct supertype *c, struct active_array *a,
diff --git a/super-intel.c b/super-intel.c
index ce9a5c1..ac0c2de 100644
--- a/super-intel.c
+++ b/super-intel.c
@@ -1101,7 +1101,7 @@ static int imsm_level_to_layout(int level)
 	case 10:
 		return 0x102;
 	}
-	return -1;
+	return UnSet;
 }
 
 static void getinfo_super_imsm_volume(struct supertype *st, struct mdinfo *info)
@@ -4143,6 +4143,7 @@ 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,
 
 	.external	= 1,
 	.name = "imsm",
-- 
cgit