From: Stephen Soltesz <soltesz@cs.princeton.edu>
Date: Fri, 21 Mar 2008 22:36:14 +0000 (+0000)
Subject: Adds a conditional check to see whether COW support is enabled in the kernel.
X-Git-Tag: VserverReference-4.2-3~4
X-Git-Url: http://git.onelab.eu/?p=vserver-reference.git;a=commitdiff_plain;h=787d86d08033f1d7fb9adf5c7e43ea6911ecd92d

Adds a conditional check to see whether COW support is enabled in the kernel.
sets the iunlink attribute accordingly.
---

diff --git a/vserver-reference.init b/vserver-reference.init
index 4458a38..1da2e99 100755
--- a/vserver-reference.init
+++ b/vserver-reference.init
@@ -57,7 +57,19 @@ setattr --barrier "$__DEFAULT_VSERVERDIR"
 
 # Set the attribute to unlink so vclone does the right thing wrt to 
 # conserving space by linking and not copying unified files.
-find "$__DEFAULT_VSERVERDIR/.vref"/* -type f -print0 | xargs -0 setattr --iunlink
+
+if [ -f /proc/virtual/info ] ; then
+	x=$[ 16#`awk '/^VCIKernel:/ { print $2 }' /proc/virtual/info` ]; 
+	y=$[ (x >> 9) & 1]
+	if test "$y" = 1 ; then 
+		# COW support
+		find "$__DEFAULT_VSERVERDIR/.vref/default" -type f -print0 | xargs -0 setattr --iunlink
+	else 
+		# no COW; 
+		find "$__DEFAULT_VSERVERDIR/.vref/default" -type f -print0 | xargs -0 setattr --~iunlink
+	fi
+fi
+
 
 # Build reference images for system slices
 # xxx if several instances of systemslices get installed, only one gets instanciated