From 0cc35251421bc5c4d5a682566e2d71b942bbcc4a Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Thu, 3 May 2012 14:31:37 +0100
Subject: [PATCH] virt-make-fs: Fix estimation when making btrfs (RHBZ#816098).

This also disables data and metadata duplication, which is not very
useful on a constructed filesystem on a virtual disk.
---
 tools/virt-make-fs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/tools/virt-make-fs b/tools/virt-make-fs
index 3938e2775..6efa3cd01 100755
--- a/tools/virt-make-fs
+++ b/tools/virt-make-fs
@@ -380,6 +380,13 @@ if ($type eq "ntfs") {
     $estimate += 4 * 1024 * 1024; # NTFS journal.
 }
 
+if ($type eq "btrfs") {
+    # For BTRFS, the minimum metadata allocation is 256MB, with data
+    # additional to that.  Note that we disable data and metadata
+    # duplication below.
+    $estimate += 256 * 1024 * 1024;
+}
+
 $estimate *= 1.10;              # Add 10%, see above.
 
 # Calculate the output size.
@@ -448,7 +455,11 @@ eval {
     print STDERR "creating $type filesystem on $dev ...\n" if $debug;
 
     # Create the filesystem.
-    $g->mkfs ($type, $dev);
+    if ($type ne "btrfs") {
+        $g->mkfs ($type, $dev);
+    } else {
+        $g->mkfs_btrfs ([$dev], datatype => "single", metadata => "single");
+    }
     $g->mount ($dev, "/");
 
     # Copy the data in.