1 files changed, 103 insertions, 0 deletions
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
new file mode 100644
index 00000000..302e0e52
--- /dev/null
+++ b/arch/s390/kvm/gaccess.h
@@ -0,0 +1,103 @@
+/*
+ * access guest memory
+ *
+ * Copyright IBM Corp. 2008, 2009
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ *    Author(s): Carsten Otte <cotte@de.ibm.com>
+ */
+
+#ifndef __KVM_S390_GACCESS_H
+#define __KVM_S390_GACCESS_H
+
+#include <linux/compiler.h>
+#include <linux/kvm_host.h>
+#include <asm/uaccess.h>
+#include "kvm-s390.h"
+
+static inline void __user *__gptr_to_uptr(struct kvm_vcpu *vcpu,
+					  void __user *gptr,
+					  int prefixing)
+{
+	unsigned long prefix  = vcpu->arch.sie_block->prefix;
+	unsigned long gaddr = (unsigned long) gptr;
+	unsigned long uaddr;
+
+	if (prefixing) {
+		if (gaddr < 2 * PAGE_SIZE)
+			gaddr += prefix;
+		else if ((gaddr >= prefix) && (gaddr < prefix + 2 * PAGE_SIZE))
+			gaddr -= prefix;
+	}
+	uaddr = gmap_fault(gaddr, vcpu->arch.gmap);
+	if (IS_ERR_VALUE(uaddr))
+		uaddr = -EFAULT;
+	return (void __user *)uaddr;
+}
+
+#define get_guest(vcpu, x, gptr)				\
+({								\
+	__typeof__(gptr) __uptr = __gptr_to_uptr(vcpu, gptr, 1);\
+	int __mask = sizeof(__typeof__(*(gptr))) - 1;		\
+	int __ret = PTR_RET((void __force *)__uptr);		\
+								\
+	if (!__ret) {						\
+		BUG_ON((unsigned long)__uptr & __mask);		\
+		__ret = get_user(x, __uptr);			\
+	}							\
+	__ret;							\
+})
+
+#define put_guest(vcpu, x, gptr)				\
+({								\
+	__typeof__(gptr) __uptr = __gptr_to_uptr(vcpu, gptr, 1);\
+	int __mask = sizeof(__typeof__(*(gptr))) - 1;		\
+	int __ret = PTR_RET((void __force *)__uptr);		\
+								\
+	if (!__ret) {						\
+		BUG_ON((unsigned long)__uptr & __mask);		\
+		__ret = put_user(x, __uptr);			\
+	}							\
+	__ret;							\
+})
+
+static inline int __copy_guest(struct kvm_vcpu *vcpu, unsigned long to,
+			       unsigned long from, unsigned long len,
+			       int to_guest, int prefixing)
+{
+	unsigned long _len, rc;
+	void __user *uptr;
+
+	while (len) {
+		uptr = to_guest ? (void __user *)to : (void __user *)from;
+		uptr = __gptr_to_uptr(vcpu, uptr, prefixing);
+		if (IS_ERR((void __force *)uptr))
+			return -EFAULT;
+		_len = PAGE_SIZE - ((unsigned long)uptr & (PAGE_SIZE - 1));
+		_len = min(_len, len);
+		if (to_guest)
+			rc = copy_to_user((void __user *) uptr, (void *)from, _len);
+		else
+			rc = copy_from_user((void *)to, (void __user *)uptr, _len);
+		if (rc)
+			return -EFAULT;
+		len -= _len;
+		from += _len;
+		to += _len;
+	}
+	return 0;
+}
+
+#define copy_to_guest(vcpu, to, from, size) \
+	__copy_guest(vcpu, to, (unsigned long)from, size, 1, 1)
+#define copy_from_guest(vcpu, to, from, size) \
+	__copy_guest(vcpu, (unsigned long)to, from, size, 0, 1)
+#define copy_to_guest_absolute(vcpu, to, from, size) \
+	__copy_guest(vcpu, to, (unsigned long)from, size, 1, 0)
+#define copy_from_guest_absolute(vcpu, to, from, size) \
+	__copy_guest(vcpu, (unsigned long)to, from, size, 0, 0)
+
+#endif /* __KVM_S390_GACCESS_H */