x86: eliminate has_arch_mmios()

... as being generally insufficient: Either has_arch_pdevs() or
cache_flush_permitted() should be used (in particular, it is
insufficient to consider MMIO ranges alone - I/O port ranges have the
same requirements if available to a guest).

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -40,6 +40,7 @@
 #include <asm/debugreg.h>
 #include <asm/msr.h>
 #include <asm/i387.h>
+#include <asm/iocap.h>
 #include <asm/spinlock.h>
 #include <asm/hvm/emulate.h>
 #include <asm/hvm/hvm.h>
@@ -1973,7 +1974,7 @@ static void wbinvd_ipi(void *info)
 
 static void svm_wbinvd_intercept(void)
 {
-    if ( has_arch_mmios(current->domain) )
+    if ( cache_flush_permitted(current->domain) )
         on_each_cpu(wbinvd_ipi, NULL, 1);
 }
 
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -28,6 +28,7 @@
 #include <xen/perfc.h>
 #include <asm/current.h>
 #include <asm/io.h>
+#include <asm/iocap.h>
 #include <asm/regs.h>
 #include <asm/cpufeature.h>
 #include <asm/processor.h>
@@ -2236,10 +2237,7 @@ static void wbinvd_ipi(void *info)
 
 static void vmx_wbinvd_intercept(void)
 {
-    if ( !has_arch_mmios(current->domain) )
-        return;
-
-    if ( iommu_snoop )
+    if ( !cache_flush_permitted(current->domain) || iommu_snoop )
         return;
 
     if ( cpu_has_wbinvd_exiting )
--- a/xen/include/asm-x86/domain.h
+++ b/xen/include/asm-x86/domain.h
@@ -316,7 +316,6 @@ struct arch_domain
 } __cacheline_aligned;
 
 #define has_arch_pdevs(d)    (!list_empty(&(d)->arch.pdev_list))
-#define has_arch_mmios(d)    (!rangeset_is_empty((d)->iomem_caps))
 
 #define gdt_ldt_pt_idx(v) \
       ((v)->vcpu_id >> (PAGETABLE_ORDER - GDT_LDT_VCPU_SHIFT))