[PATCH v3 06/15] xen/mem_event: Abstract architecture specific sanity checks

[Tamas K Lengyel <tklengyel@sec.in.tum.de>]

Move architecture specific sanity checks into its own function
which is called when enabling mem_event.

Signed-off-by: Tamas K Lengyel <tklengyel@sec.in.tum.de>
---
v2: Move sanity check function into architecture specific p2m.h
---
 xen/common/mem_event.c    | 11 ++++-------
 xen/include/asm-x86/p2m.h | 14 ++++++++++++++
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/xen/common/mem_event.c b/xen/common/mem_event.c
index f0feedd..584de16 100644
--- a/xen/common/mem_event.c
+++ b/xen/common/mem_event.c
@@ -592,14 +592,11 @@ int mem_event_domctl(struct domain *d, xen_domctl_mem_event_op_t *mec,
         {
         case XEN_DOMCTL_MEM_EVENT_OP_ACCESS_ENABLE:
         {
-            rc = -ENODEV;
-            /* Only HAP is supported */
-            if ( !hap_enabled(d) )
-                break;
-
-            /* Currently only EPT is supported */
-            if ( !cpu_has_vmx )
+            if ( !p2m_mem_event_sanity_check(d) )
+            {
+                rc = -ENODEV;
                 break;
+            }
 
             rc = mem_event_enable(d, mec, med, _VPF_mem_access,
                                     HVM_PARAM_ACCESS_RING_PFN,
diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h
index 3975e32..9a1fae3 100644
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -613,6 +613,20 @@ long p2m_set_mem_access(struct domain *d, unsigned long start_pfn, uint32_t nr,
 int p2m_get_mem_access(struct domain *d, unsigned long pfn,
                        xenmem_access_t *access);
 
+/* Sanity check for mem_event hardware support */
+static inline bool_t p2m_mem_event_sanity_check(struct domain *d)
+{
+    /* Only HAP is supported */
+    if ( !hap_enabled(d) )
+        return 0;
+
+    /* Currently only EPT is supported */
+    if ( !cpu_has_vmx )
+        return 0;
+
+    return 1;
+}
+
 /* 
  * Internal functions, only called by other p2m code
  */
-- 
2.1.0.rc1