From d1718e7d2bedd4089cadfb66c288e14c43ffa1c5 Mon Sep 17 00:00:00 2001
From: Vladimir 'phcoder' Serbinenko <phcoder@gmail.com>
Date: Fri, 22 Jun 2012 22:11:23 +0200
Subject: [PATCH] 	* util/getroot.c
 (grub_find_root_devices_from_mountinfo): Handle btrfs 	subvolumes.

---
 ChangeLog      |  5 +++++
 util/getroot.c | 16 +++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index c12da1a0c..e2d5e0f0c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2012-06-22  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* util/getroot.c (grub_find_root_devices_from_mountinfo): Handle btrfs
+	subvolumes.
+
 2012-06-22  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	Implement flow control for http.
diff --git a/util/getroot.c b/util/getroot.c
index cbcd3aa5f..e103fb6c1 100644
--- a/util/getroot.c
+++ b/util/getroot.c
@@ -651,7 +651,21 @@ grub_find_root_devices_from_mountinfo (const char *dir, char **relroot)
 	{
 	  ret = grub_find_root_devices_from_btrfs (dir);
 	  if (relroot)
-	    *relroot = strdup (entries[i].enc_root);
+	    {
+	      char *ptr;
+	      *relroot = xmalloc (strlen (entries[i].enc_root) +
+				  2 + strlen (dir));
+	      ptr = stpcpy (*relroot, entries[i].enc_root);
+	      if (strlen (dir) > strlen (entries[i].enc_path))
+		{
+		  while (ptr > *relroot && *(ptr - 1) == '/')
+		    ptr--;
+		  if (dir[strlen (entries[i].enc_path)] != '/')
+		    *ptr++ = '/';
+		  ptr = stpcpy (ptr, dir + strlen (entries[i].enc_path));
+		}
+	      *ptr = 0;
+	    }
 	}
       if (!ret)
 	{