From 732e563373ffc57d38a8a3b6d55f2de865182117 Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@linux.vnet.ibm.com>
Date: Thu, 12 Sep 2013 10:33:47 +0200
Subject: [PATCH] KVM: s390: Helper for converting real addresses to absolute
Added a separate helper function that translates guest real addresses
to guest absolute addresses by applying the prefix of the guest CPU.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/s390/kvm/gaccess.h | 21 ++++++++++++++-------
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index 99d789e8a0189..374a439ccc608 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -18,20 +18,27 @@
#include <asm/uaccess.h>
#include "kvm-s390.h"
+/* Convert real to absolute address by applying the prefix of the CPU */
+static inline unsigned long kvm_s390_real_to_abs(struct kvm_vcpu *vcpu,
+ unsigned long gaddr)
+{
+ unsigned long prefix = vcpu->arch.sie_block->prefix;
+ if (gaddr < 2 * PAGE_SIZE)
+ gaddr += prefix;
+ else if (gaddr >= prefix && gaddr < prefix + 2 * PAGE_SIZE)
+ gaddr -= prefix;
+ return gaddr;
+}
+
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;
- }
+ if (prefixing)
+ gaddr = kvm_s390_real_to_abs(vcpu, gaddr);
uaddr = gmap_fault(gaddr, vcpu->arch.gmap);
if (IS_ERR_VALUE(uaddr))
uaddr = -EFAULT;
--
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