From 754e414742e0d68d8afec6de143e7bbb0a2908e3 Mon Sep 17 00:00:00 2001
From: Anders Ingemann <anders@ingemann.de>
Date: Tue, 8 Oct 2013 23:12:03 +0200
Subject: [PATCH] Document post-mbr gap and make it MBR-only

---
 base/fs/partitionmaps/abstract.py | 2 +-
 base/fs/partitionmaps/mbr.py      | 3 +++
 base/fs/partitions/base.py        | 2 +-
 base/fs/partitions/mbr.py         | 6 ++++++
 4 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/base/fs/partitionmaps/abstract.py b/base/fs/partitionmaps/abstract.py
index f26b970..bac76c4 100644
--- a/base/fs/partitionmaps/abstract.py
+++ b/base/fs/partitionmaps/abstract.py
@@ -22,7 +22,7 @@ class AbstractPartitionMap(FSMProxy):
 		return self.fsm.current == 'mapped'
 
 	def get_total_size(self):
-		return sum(p.size for p in self.partitions) + 1
+		return sum(p.size for p in self.partitions)
 
 	def create(self, volume):
 		self.fsm.create(volume=volume)
diff --git a/base/fs/partitionmaps/mbr.py b/base/fs/partitionmaps/mbr.py
index 0d4b50f..d2d8a8d 100644
--- a/base/fs/partitionmaps/mbr.py
+++ b/base/fs/partitionmaps/mbr.py
@@ -19,6 +19,9 @@ class MBRPartitionMap(AbstractPartitionMap):
 
 		super(MBRPartitionMap, self).__init__()
 
+	def get_total_size(self):
+		return sum(p.size for p in self.partitions) + 1  # Post-MBR gap for embedding grub
+
 	def _before_create(self, event):
 		volume = event.volume
 		log_check_call(['/sbin/parted', '--script', '--align', 'none', volume.device_path,
diff --git a/base/fs/partitions/base.py b/base/fs/partitions/base.py
index 8986285..0769de5 100644
--- a/base/fs/partitions/base.py
+++ b/base/fs/partitions/base.py
@@ -26,7 +26,7 @@ class BasePartition(AbstractPartition):
 
 	def get_start(self):
 		if self.previous is None:
-			return 1
+			return 0
 		else:
 			return self.previous.get_start() + self.previous.size
 
diff --git a/base/fs/partitions/mbr.py b/base/fs/partitions/mbr.py
index 511cd10..d10c2d8 100644
--- a/base/fs/partitions/mbr.py
+++ b/base/fs/partitions/mbr.py
@@ -4,6 +4,12 @@ from base import BasePartition
 
 class MBRPartition(BasePartition):
 
+	def get_start(self):
+		if self.previous is None:
+			return 1  # Post-MBR gap for embedding grub
+		else:
+			return self.previous.get_start() + self.previous.size
+
 	def _before_create(self, e):
 		start = self.get_start()
 		parted_command = ('mkpart primary {start}MiB {end}MiB'