[PATCH 1 of 3] xenpaging: Add a check to Xen for EPT

[Patrick Colp <pjcolp@cs.ubc.ca>]

# HG changeset patch
# User Patrick Colp <pjcolp@cs.ubc.ca>
# Date 1280265109 25200
# Node ID 6cb61775657f6ea362b3ff45ed22e67b00ad3ea5
# Parent  ac7e4c6ec6c7494e4046da92aa8f62f6c1371438
xenpaging: Add a check to Xen for EPT.

There isn't seem to be a way to directly check for EPT, so instead check for
HAP and an Intel processor. If EPT isn't enabled, then return an error to the
tool.

Signed-off-by: Patrick Colp <pjcolp@cs.ubc.ca>

diff -r ac7e4c6ec6c7 -r 6cb61775657f xen/arch/x86/mm/mem_event.c
--- a/xen/arch/x86/mm/mem_event.c	Fri Jul 23 19:23:49 2010 +0100
+++ b/xen/arch/x86/mm/mem_event.c	Tue Jul 27 14:11:49 2010 -0700
@@ -21,6 +21,7 @@
  */
 
 
+#include <asm/domain.h>
 #include <xen/event.h>
 #include <asm/p2m.h>
 #include <asm/mem_event.h>
@@ -225,6 +226,12 @@
             mfn_t ring_mfn;
             mfn_t shared_mfn;
 
+            /* Currently only EPT is supported */
+            rc = -ENODEV;
+            if ( !(hap_enabled(d) &&
+                  (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)) )
+                break;
+
             /* Get MFN of ring page */
             guest_get_eff_l1e(v, ring_addr, &l1e);
             gfn = l1e_get_pfn(l1e);