vm/dispvm: use of user-provided DispVM settings (#651)

When /rw/home/user/.qubes-dispvm-customized is present use /rw/home/user
instead of default /etc/dispvm-dotfiles.tbz. Also make sure that /rw will not
remain mounted during DispVM creation.

misc/dispvm-prerun.sh

@@ -2,7 +2,12 @@
 
 apps="evince /usr/libexec/evinced soffice firefox"
 
-cat /etc/dispvm-dotfiles.tbz | tar -xjf- --overwrite -C /home/user --owner user 2>&1 >/tmp/dispvm-dotfiles-errors.log
+#If user have customized DispVM settings, use its home instead of default dotfiles
+if [ -e /rw/home/user/.qubes-dispvm-customized ]; then
+	cp -af /rw/home/user /home/
+else
+	cat /etc/dispvm-dotfiles.tbz | tar -xjf- --overwrite -C /home/user --owner user 2>&1 >/tmp/dispvm-dotfiles-errors.log
+fi
 
 for app in $apps ; do
     echo "Launching: $app..."
@@ -22,6 +27,10 @@ done
 
 ps ax > /tmp/dispvm-prerun-proclist.log
 
-cat /etc/dispvm-dotfiles.tbz | tar -xjf- --overwrite -C /home/user --owner user 2>&1 >>/tmp/dispvm-dotfiles-errors.log
+if [ -e /rw/home/user/.qubes-dispvm-customized ]; then
+	cp -af /rw/home/user /home/
+else
+	cat /etc/dispvm-dotfiles.tbz | tar -xjf- --overwrite -C /home/user --owner user 2>&1 >>/tmp/dispvm-dotfiles-errors.log
+fi
 
 echo done.

vm-init.d/qubes_core_appvm

@@ -46,8 +46,10 @@ start()
 
 	if xenstore-read qubes_save_request 2>/dev/null ; then
 		ln -sf /home_volatile /home
-		possibly_run_save_script 
 		touch /etc/this_is_dvm
+		mount /rw
+		possibly_run_save_script
+		umount /rw
 		dmesg -c >/dev/null
 		free | grep Mem: | 
 			(read a b c d ; xenstore-write device/qubes_used_mem $c)

vm-systemd/misc-post.sh

@@ -12,7 +12,7 @@ fi
 # xenstore-read fails
 INTERFACE=eth0 /usr/lib/qubes/setup_ip
 
-if [ -e /dev/xvdb ] ; then
+if [ -e /dev/xvdb -a ! -e /etc/this_is_dvm ] ; then
     mount /rw
 
     if ! [ -d /rw/home ] ; then

vm-systemd/prepare-dvm.sh

@@ -14,8 +14,10 @@ possibly_run_save_script()
 
 if xenstore-read qubes_save_request 2>/dev/null ; then
     ln -sf /home_volatile /home
-    possibly_run_save_script 
     touch /etc/this_is_dvm
+    mount /rw
+    possibly_run_save_script
+    umount /rw
     dmesg -c >/dev/null
     free | grep Mem: | 
         (read a b c d ; xenstore-write device/qubes_used_mem $c)