2 files changed, 16 insertions, 0 deletions

diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h
index c34f96c2f7a0..93971e841dd5 100644
--- a/arch/x86/include/asm/xen/page.h
+++ b/arch/x86/include/asm/xen/page.h
@@ -44,6 +44,7 @@ extern unsigned long  machine_to_phys_nr;
 
 extern unsigned long get_phys_to_machine(unsigned long pfn);
 extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
+extern bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn);
 extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
 extern unsigned long set_phys_range_identity(unsigned long pfn_s,
                                              unsigned long pfn_e);
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 952edefcedb3..ffd08c414e91 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -570,6 +570,21 @@ static bool __init early_alloc_p2m(unsigned long pfn)
         }
         return true;
 }
+bool __init early_set_phys_to_machine(unsigned long pfn, unsigned long mfn)
+{
+        if (unlikely(!__set_phys_to_machine(pfn, mfn)))  {
+                if (!early_alloc_p2m(pfn))
+                        return false;
+
+                if (!early_alloc_p2m_middle(pfn, false /* boundary crossover OK!*/))
+                        return false;
+
+                if (!__set_phys_to_machine(pfn, mfn))
+                        return false;
+        }
+
+        return true;
+}
 unsigned long __init set_phys_range_identity(unsigned long pfn_s,
                                       unsigned long pfn_e)
 {