3 files changed, 31 insertions, 3 deletions
diff --git a/arch/arm/include/asm/xen/events.h b/arch/arm/include/asm/xen/events.h
index 94b4e90..5c27696 100644
--- a/arch/arm/include/asm/xen/events.h
+++ b/arch/arm/include/asm/xen/events.h
@@ -15,4 +15,26 @@ static inline int xen_irqs_disabled(struct pt_regs *regs)
 	return raw_irqs_disabled_flags(regs->ARM_cpsr);
 }
 
+/*
+ * We cannot use xchg because it does not support 8-byte
+ * values. However it is safe to use {ldr,dtd}exd directly because all
+ * platforms which Xen can run on support those instructions.
+ */
+static inline xen_ulong_t xchg_xen_ulong(xen_ulong_t *ptr, xen_ulong_t val)
+{
+	xen_ulong_t oldval;
+	unsigned int tmp;
+
+	wmb();
+	asm volatile("@ xchg_xen_ulong\n"
+		"1:     ldrexd  %0, %H0, [%3]\n"
+		"       strexd  %1, %2, %H2, [%3]\n"
+		"       teq     %1, #0\n"
+		"       bne     1b"
+		: "=&r" (oldval), "=&r" (tmp)
+		: "r" (val), "r" (ptr)
+		: "memory", "cc");
+	return oldval;
+}
+
 #endif /* _ASM_ARM_XEN_EVENTS_H */
diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h
index c6b9096..30cdacb 100644
--- a/arch/arm/include/asm/xen/page.h
+++ b/arch/arm/include/asm/xen/page.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_ARM_XEN_PAGE_H
 #define _ASM_ARM_XEN_PAGE_H
 
+#include <asm/mach/map.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
 
@@ -86,4 +87,7 @@ static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
 {
 	return __set_phys_to_machine(pfn, mfn);
 }
+
+#define xen_remap(cookie, size) __arm_ioremap((cookie), (size), MT_MEMORY);
+
 #endif /* _ASM_ARM_XEN_PAGE_H */
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 7a32976..8dc0605 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -59,14 +59,16 @@ static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
 	};
 	xen_ulong_t idx = fgmfn;
 	xen_pfn_t gpfn = lpfn;
+	int err = 0;
 
 	set_xen_guest_handle(xatp.idxs, &idx);
 	set_xen_guest_handle(xatp.gpfns, &gpfn);
+	set_xen_guest_handle(xatp.errs, &err);
 
 	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
-	if (rc) {
-		pr_warn("Failed to map pfn to mfn rc:%d pfn:%lx mfn:%lx\n",
-			rc, lpfn, fgmfn);
+	if (rc || err) {
+		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
+			rc, err, lpfn, fgmfn);
 		return 1;
 	}
 	return 0;