xen/x86: convert pv_guest_cr4_to_real_cr4() to a function

pv_guest_cr4_to_real_cr4() is becoming more and more complex. Convert
it from a macro to an ordinary function.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

xen/arch/x86/mm.c

@@ -506,6 +506,20 @@ void make_cr3(struct vcpu *v, mfn_t mfn)
     v->arch.cr3 = mfn_x(mfn) << PAGE_SHIFT;
 }
 
+unsigned long pv_guest_cr4_to_real_cr4(const struct vcpu *v)
+{
+    const struct domain *d = v->domain;
+    unsigned long cr4;
+
+    cr4 = v->arch.pv_vcpu.ctrlreg[4] & ~X86_CR4_DE;
+    cr4 |= mmu_cr4_features & (X86_CR4_PSE | X86_CR4_SMEP | X86_CR4_SMAP |
+                               X86_CR4_OSXSAVE | X86_CR4_FSGSBASE);
+    cr4 |= d->arch.pv_domain.xpti  ? 0 : X86_CR4_PGE;
+    cr4 |= d->arch.vtsc ? X86_CR4_TSD : 0;
+
+    return cr4;
+}
+
 void write_ptbase(struct vcpu *v)
 {
     struct cpu_info *cpu_info = get_cpu_info();

xen/include/asm-x86/domain.h

@@ -615,15 +615,8 @@ void vcpu_show_registers(const struct vcpu *);
 unsigned long pv_guest_cr4_fixup(const struct vcpu *, unsigned long guest_cr4);
 
 /* Convert between guest-visible and real CR4 values. */
-#define pv_guest_cr4_to_real_cr4(v)                         \
-    (((v)->arch.pv_vcpu.ctrlreg[4]                          \
-      | (mmu_cr4_features                                   \
-         & (X86_CR4_PSE | X86_CR4_SMEP |                    \
-            X86_CR4_SMAP | X86_CR4_OSXSAVE |                \
-            X86_CR4_FSGSBASE))                              \
-      | ((v)->domain->arch.pv_domain.xpti ? 0 : X86_CR4_PGE) \
-      | ((v)->domain->arch.vtsc ? X86_CR4_TSD : 0))         \
-     & ~X86_CR4_DE)
+unsigned long pv_guest_cr4_to_real_cr4(const struct vcpu *v);
+
 #define real_cr4_to_pv_guest_cr4(c)                         \
     ((c) & ~(X86_CR4_PGE | X86_CR4_PSE | X86_CR4_TSD |      \
              X86_CR4_OSXSAVE | X86_CR4_SMEP |               \