diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index d3adb37e93a4..83a7a355befe 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -11,5 +11,7 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o  $(KVM)/async_pf.o $(KVM)/irqch
 
 ccflags-y := -Ivirt/kvm -Iarch/s390/kvm
 
-kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o diag.o
+kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o
+kvm-objs += diag.o gaccess.o
+
 obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
new file mode 100644
index 000000000000..916e1ee1f8c9
--- /dev/null
+++ b/arch/s390/kvm/gaccess.c
@@ -0,0 +1,536 @@
+/*
+ * guest access functions
+ *
+ * Copyright IBM Corp. 2014
+ *
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/err.h>
+#include <asm/pgtable.h>
+#include "kvm-s390.h"
+#include "gaccess.h"
+
+union asce {
+	unsigned long val;
+	struct {
+		unsigned long origin : 52; /* Region- or Segment-Table Origin */
+		unsigned long	 : 2;
+		unsigned long g  : 1; /* Subspace Group Control */
+		unsigned long p  : 1; /* Private Space Control */
+		unsigned long s  : 1; /* Storage-Alteration-Event Control */
+		unsigned long x  : 1; /* Space-Switch-Event Control */
+		unsigned long r  : 1; /* Real-Space Control */
+		unsigned long	 : 1;
+		unsigned long dt : 2; /* Designation-Type Control */
+		unsigned long tl : 2; /* Region- or Segment-Table Length */
+	};
+};
+
+enum {
+	ASCE_TYPE_SEGMENT = 0,
+	ASCE_TYPE_REGION3 = 1,
+	ASCE_TYPE_REGION2 = 2,
+	ASCE_TYPE_REGION1 = 3
+};
+
+union region1_table_entry {
+	unsigned long val;
+	struct {
+		unsigned long rto: 52;/* Region-Table Origin */
+		unsigned long	 : 2;
+		unsigned long p  : 1; /* DAT-Protection Bit */
+		unsigned long	 : 1;
+		unsigned long tf : 2; /* Region-Second-Table Offset */
+		unsigned long i  : 1; /* Region-Invalid Bit */
+		unsigned long	 : 1;
+		unsigned long tt : 2; /* Table-Type Bits */
+		unsigned long tl : 2; /* Region-Second-Table Length */
+	};
+};
+
+union region2_table_entry {
+	unsigned long val;
+	struct {
+		unsigned long rto: 52;/* Region-Table Origin */
+		unsigned long	 : 2;
+		unsigned long p  : 1; /* DAT-Protection Bit */
+		unsigned long	 : 1;
+		unsigned long tf : 2; /* Region-Third-Table Offset */
+		unsigned long i  : 1; /* Region-Invalid Bit */
+		unsigned long	 : 1;
+		unsigned long tt : 2; /* Table-Type Bits */
+		unsigned long tl : 2; /* Region-Third-Table Length */
+	};
+};
+
+struct region3_table_entry_fc0 {
+	unsigned long sto: 52;/* Segment-Table Origin */
+	unsigned long	 : 1;
+	unsigned long fc : 1; /* Format-Control */
+	unsigned long p  : 1; /* DAT-Protection Bit */
+	unsigned long	 : 1;
+	unsigned long tf : 2; /* Segment-Table Offset */
+	unsigned long i  : 1; /* Region-Invalid Bit */
+	unsigned long cr : 1; /* Common-Region Bit */
+	unsigned long tt : 2; /* Table-Type Bits */
+	unsigned long tl : 2; /* Segment-Table Length */
+};
+
+struct region3_table_entry_fc1 {
+	unsigned long rfaa : 33; /* Region-Frame Absolute Address */
+	unsigned long	 : 14;
+	unsigned long av : 1; /* ACCF-Validity Control */
+	unsigned long acc: 4; /* Access-Control Bits */
+	unsigned long f  : 1; /* Fetch-Protection Bit */
+	unsigned long fc : 1; /* Format-Control */
+	unsigned long p  : 1; /* DAT-Protection Bit */
+	unsigned long co : 1; /* Change-Recording Override */
+	unsigned long	 : 2;
+	unsigned long i  : 1; /* Region-Invalid Bit */
+	unsigned long cr : 1; /* Common-Region Bit */
+	unsigned long tt : 2; /* Table-Type Bits */
+	unsigned long	 : 2;
+};
+
+union region3_table_entry {
+	unsigned long val;
+	struct region3_table_entry_fc0 fc0;
+	struct region3_table_entry_fc1 fc1;
+	struct {
+		unsigned long	 : 53;
+		unsigned long fc : 1; /* Format-Control */
+		unsigned long	 : 4;
+		unsigned long i  : 1; /* Region-Invalid Bit */
+		unsigned long cr : 1; /* Common-Region Bit */
+		unsigned long tt : 2; /* Table-Type Bits */
+		unsigned long	 : 2;
+	};
+};
+
+struct segment_entry_fc0 {
+	unsigned long pto: 53;/* Page-Table Origin */
+	unsigned long fc : 1; /* Format-Control */
+	unsigned long p  : 1; /* DAT-Protection Bit */
+	unsigned long	 : 3;
+	unsigned long i  : 1; /* Segment-Invalid Bit */
+	unsigned long cs : 1; /* Common-Segment Bit */
+	unsigned long tt : 2; /* Table-Type Bits */
+	unsigned long	 : 2;
+};
+
+struct segment_entry_fc1 {
+	unsigned long sfaa : 44; /* Segment-Frame Absolute Address */
+	unsigned long	 : 3;
+	unsigned long av : 1; /* ACCF-Validity Control */
+	unsigned long acc: 4; /* Access-Control Bits */
+	unsigned long f  : 1; /* Fetch-Protection Bit */
+	unsigned long fc : 1; /* Format-Control */
+	unsigned long p  : 1; /* DAT-Protection Bit */
+	unsigned long co : 1; /* Change-Recording Override */
+	unsigned long	 : 2;
+	unsigned long i  : 1; /* Segment-Invalid Bit */
+	unsigned long cs : 1; /* Common-Segment Bit */
+	unsigned long tt : 2; /* Table-Type Bits */
+	unsigned long	 : 2;
+};
+
+union segment_table_entry {
+	unsigned long val;
+	struct segment_entry_fc0 fc0;
+	struct segment_entry_fc1 fc1;
+	struct {
+		unsigned long	 : 53;
+		unsigned long fc : 1; /* Format-Control */
+		unsigned long	 : 4;
+		unsigned long i  : 1; /* Segment-Invalid Bit */
+		unsigned long cs : 1; /* Common-Segment Bit */
+		unsigned long tt : 2; /* Table-Type Bits */
+		unsigned long	 : 2;
+	};
+};
+
+enum {
+	TABLE_TYPE_SEGMENT = 0,
+	TABLE_TYPE_REGION3 = 1,
+	TABLE_TYPE_REGION2 = 2,
+	TABLE_TYPE_REGION1 = 3
+};
+
+union page_table_entry {
+	unsigned long val;
+	struct {
+		unsigned long pfra : 52; /* Page-Frame Real Address */
+		unsigned long z  : 1; /* Zero Bit */
+		unsigned long i  : 1; /* Page-Invalid Bit */
+		unsigned long p  : 1; /* DAT-Protection Bit */
+		unsigned long co : 1; /* Change-Recording Override */
+		unsigned long	 : 8;
+	};
+};
+
+/*
+ * vaddress union in order to easily decode a virtual address into its
+ * region first index, region second index etc. parts.
+ */
+union vaddress {
+	unsigned long addr;
+	struct {
+		unsigned long rfx : 11;
+		unsigned long rsx : 11;
+		unsigned long rtx : 11;
+		unsigned long sx  : 11;
+		unsigned long px  : 8;
+		unsigned long bx  : 12;
+	};
+	struct {
+		unsigned long rfx01 : 2;
+		unsigned long	    : 9;
+		unsigned long rsx01 : 2;
+		unsigned long	    : 9;
+		unsigned long rtx01 : 2;
+		unsigned long	    : 9;
+		unsigned long sx01  : 2;
+		unsigned long	    : 29;
+	};
+};
+
+/*
+ * raddress union which will contain the result (real or absolute address)
+ * after a page table walk. The rfaa, sfaa and pfra members are used to
+ * simply assign them the value of a region, segment or page table entry.
+ */
+union raddress {
+	unsigned long addr;
+	unsigned long rfaa : 33; /* Region-Frame Absolute Address */
+	unsigned long sfaa : 44; /* Segment-Frame Absolute Address */
+	unsigned long pfra : 52; /* Page-Frame Real Address */
+};
+
+static unsigned long get_vcpu_asce(struct kvm_vcpu *vcpu)
+{
+	switch (psw_bits(vcpu->arch.sie_block->gpsw).as) {
+	case PSW_AS_PRIMARY:
+		return vcpu->arch.sie_block->gcr[1];
+	case PSW_AS_SECONDARY:
+		return vcpu->arch.sie_block->gcr[7];
+	case PSW_AS_HOME:
+		return vcpu->arch.sie_block->gcr[13];
+	}
+	return 0;
+}
+
+static int deref_table(struct kvm *kvm, unsigned long gpa, unsigned long *val)
+{
+	return kvm_read_guest(kvm, gpa, val, sizeof(*val));
+}
+
+/**
+ * guest_translate - translate a guest virtual into a guest absolute address
+ * @vcpu: virtual cpu
+ * @gva: guest virtual address
+ * @gpa: points to where guest physical (absolute) address should be stored
+ * @write: indicates if access is a write access
+ *
+ * Translate a guest virtual address into a guest absolute address by means
+ * of dynamic address translation as specified by the architecuture.
+ * If the resulting absolute address is not available in the configuration
+ * an addressing exception is indicated and @gpa will not be changed.
+ *
+ * Returns: - zero on success; @gpa contains the resulting absolute address
+ *	    - a negative value if guest access failed due to e.g. broken
+ *	      guest mapping
+ *	    - a positve value if an access exception happened. In this case
+ *	      the returned value is the program interruption code as defined
+ *	      by the architecture
+ */
+static unsigned long guest_translate(struct kvm_vcpu *vcpu, unsigned long gva,
+				     unsigned long *gpa, int write)
+{
+	union vaddress vaddr = {.addr = gva};
+	union raddress raddr = {.addr = gva};
+	union page_table_entry pte;
+	int dat_protection = 0;
+	union ctlreg0 ctlreg0;
+	unsigned long ptr;
+	int edat1, edat2;
+	union asce asce;
+
+	ctlreg0.val = vcpu->arch.sie_block->gcr[0];
+	edat1 = ctlreg0.edat && test_vfacility(8);
+	edat2 = edat1 && test_vfacility(78);
+	asce.val = get_vcpu_asce(vcpu);
+	if (asce.r)
+		goto real_address;
+	ptr = asce.origin * 4096;
+	switch (asce.dt) {
+	case ASCE_TYPE_REGION1:
+		if (vaddr.rfx01 > asce.tl)
+			return PGM_REGION_FIRST_TRANS;
+		ptr += vaddr.rfx * 8;
+		break;
+	case ASCE_TYPE_REGION2:
+		if (vaddr.rfx)
+			return PGM_ASCE_TYPE;
+		if (vaddr.rsx01 > asce.tl)
+			return PGM_REGION_SECOND_TRANS;
+		ptr += vaddr.rsx * 8;
+		break;
+	case ASCE_TYPE_REGION3:
+		if (vaddr.rfx || vaddr.rsx)
+			return PGM_ASCE_TYPE;
+		if (vaddr.rtx01 > asce.tl)
+			return PGM_REGION_THIRD_TRANS;
+		ptr += vaddr.rtx * 8;
+		break;
+	case ASCE_TYPE_SEGMENT:
+		if (vaddr.rfx || vaddr.rsx || vaddr.rtx)
+			return PGM_ASCE_TYPE;
+		if (vaddr.sx01 > asce.tl)
+			return PGM_SEGMENT_TRANSLATION;
+		ptr += vaddr.sx * 8;
+		break;
+	}
+	switch (asce.dt) {
+	case ASCE_TYPE_REGION1:	{
+		union region1_table_entry rfte;
+
+		if (kvm_is_error_gpa(vcpu->kvm, ptr))
+			return PGM_ADDRESSING;
+		if (deref_table(vcpu->kvm, ptr, &rfte.val))
+			return -EFAULT;
+		if (rfte.i)
+			return PGM_REGION_FIRST_TRANS;
+		if (rfte.tt != TABLE_TYPE_REGION1)
+			return PGM_TRANSLATION_SPEC;
+		if (vaddr.rsx01 < rfte.tf || vaddr.rsx01 > rfte.tl)
+			return PGM_REGION_SECOND_TRANS;
+		if (edat1)
+			dat_protection |= rfte.p;
+		ptr = rfte.rto * 4096 + vaddr.rsx * 8;
+	}
+		/* fallthrough */
+	case ASCE_TYPE_REGION2: {
+		union region2_table_entry rste;
+
+		if (kvm_is_error_gpa(vcpu->kvm, ptr))
+			return PGM_ADDRESSING;
+		if (deref_table(vcpu->kvm, ptr, &rste.val))
+			return -EFAULT;
+		if (rste.i)
+			return PGM_REGION_SECOND_TRANS;
+		if (rste.tt != TABLE_TYPE_REGION2)
+			return PGM_TRANSLATION_SPEC;
+		if (vaddr.rtx01 < rste.tf || vaddr.rtx01 > rste.tl)
+			return PGM_REGION_THIRD_TRANS;
+		if (edat1)
+			dat_protection |= rste.p;
+		ptr = rste.rto * 4096 + vaddr.rtx * 8;
+	}
+		/* fallthrough */
+	case ASCE_TYPE_REGION3: {
+		union region3_table_entry rtte;
+
+		if (kvm_is_error_gpa(vcpu->kvm, ptr))
+			return PGM_ADDRESSING;
+		if (deref_table(vcpu->kvm, ptr, &rtte.val))
+			return -EFAULT;
+		if (rtte.i)
+			return PGM_REGION_THIRD_TRANS;
+		if (rtte.tt != TABLE_TYPE_REGION3)
+			return PGM_TRANSLATION_SPEC;
+		if (rtte.cr && asce.p && edat2)
+			return PGM_TRANSLATION_SPEC;
+		if (rtte.fc && edat2) {
+			dat_protection |= rtte.fc1.p;
+			raddr.rfaa = rtte.fc1.rfaa;
+			goto absolute_address;
+		}
+		if (vaddr.sx01 < rtte.fc0.tf)
+			return PGM_SEGMENT_TRANSLATION;
+		if (vaddr.sx01 > rtte.fc0.tl)
+			return PGM_SEGMENT_TRANSLATION;
+		if (edat1)
+			dat_protection |= rtte.fc0.p;
+		ptr = rtte.fc0.sto * 4096 + vaddr.sx * 8;
+	}
+		/* fallthrough */
+	case ASCE_TYPE_SEGMENT: {
+		union segment_table_entry ste;
+
+		if (kvm_is_error_gpa(vcpu->kvm, ptr))
+			return PGM_ADDRESSING;
+		if (deref_table(vcpu->kvm, ptr, &ste.val))
+			return -EFAULT;
+		if (ste.i)
+			return PGM_SEGMENT_TRANSLATION;
+		if (ste.tt != TABLE_TYPE_SEGMENT)
+			return PGM_TRANSLATION_SPEC;
+		if (ste.cs && asce.p)
+			return PGM_TRANSLATION_SPEC;
+		if (ste.fc && edat1) {
+			dat_protection |= ste.fc1.p;
+			raddr.sfaa = ste.fc1.sfaa;
+			goto absolute_address;
+		}
+		dat_protection |= ste.fc0.p;
+		ptr = ste.fc0.pto * 2048 + vaddr.px * 8;
+	}
+	}
+	if (kvm_is_error_gpa(vcpu->kvm, ptr))
+		return PGM_ADDRESSING;
+	if (deref_table(vcpu->kvm, ptr, &pte.val))
+		return -EFAULT;
+	if (pte.i)
+		return PGM_PAGE_TRANSLATION;
+	if (pte.z)
+		return PGM_TRANSLATION_SPEC;
+	if (pte.co && !edat1)
+		return PGM_TRANSLATION_SPEC;
+	dat_protection |= pte.p;
+	raddr.pfra = pte.pfra;
+real_address:
+	raddr.addr = kvm_s390_real_to_abs(vcpu, raddr.addr);
+absolute_address:
+	if (write && dat_protection)
+		return PGM_PROTECTION;
+	if (kvm_is_error_gpa(vcpu->kvm, raddr.addr))
+		return PGM_ADDRESSING;
+	*gpa = raddr.addr;
+	return 0;
+}
+
+static inline int is_low_address(unsigned long ga)
+{
+	/* Check for address ranges 0..511 and 4096..4607 */
+	return (ga & ~0x11fful) == 0;
+}
+
+static int low_address_protection_enabled(struct kvm_vcpu *vcpu)
+{
+	union ctlreg0 ctlreg0 = {.val = vcpu->arch.sie_block->gcr[0]};
+	psw_t *psw = &vcpu->arch.sie_block->gpsw;
+	union asce asce;
+
+	if (!ctlreg0.lap)
+		return 0;
+	asce.val = get_vcpu_asce(vcpu);
+	if (psw_bits(*psw).t && asce.p)
+		return 0;
+	return 1;
+}
+
+struct trans_exc_code_bits {
+	unsigned long addr : 52; /* Translation-exception Address */
+	unsigned long fsi  : 2;  /* Access Exception Fetch/Store Indication */
+	unsigned long	   : 7;
+	unsigned long b61  : 1;
+	unsigned long as   : 2;  /* ASCE Identifier */
+};
+
+enum {
+	FSI_UNKNOWN = 0, /* Unknown wether fetch or store */
+	FSI_STORE   = 1, /* Exception was due to store operation */
+	FSI_FETCH   = 2  /* Exception was due to fetch operation */
+};
+
+static int guest_page_range(struct kvm_vcpu *vcpu, unsigned long ga,
+			    unsigned long *pages, unsigned long nr_pages,
+			    int write)
+{
+	struct kvm_s390_pgm_info *pgm = &vcpu->arch.pgm;
+	psw_t *psw = &vcpu->arch.sie_block->gpsw;
+	struct trans_exc_code_bits *tec_bits;
+	int lap_enabled, rc;
+
+	memset(pgm, 0, sizeof(*pgm));
+	tec_bits = (struct trans_exc_code_bits *)&pgm->trans_exc_code;
+	tec_bits->fsi = write ? FSI_STORE : FSI_FETCH;
+	tec_bits->as = psw_bits(*psw).as;
+	lap_enabled = low_address_protection_enabled(vcpu);
+	while (nr_pages) {
+		ga = kvm_s390_logical_to_effective(vcpu, ga);
+		tec_bits->addr = ga >> PAGE_SHIFT;
+		if (write && lap_enabled && is_low_address(ga)) {
+			pgm->code = PGM_PROTECTION;
+			return pgm->code;
+		}
+		ga &= PAGE_MASK;
+		if (psw_bits(*psw).t) {
+			rc = guest_translate(vcpu, ga, pages, write);
+			if (rc < 0)
+				return rc;
+			if (rc == PGM_PROTECTION)
+				tec_bits->b61 = 1;
+			if (rc)
+				pgm->code = rc;
+		} else {
+			*pages = kvm_s390_real_to_abs(vcpu, ga);
+			if (kvm_is_error_gpa(vcpu->kvm, *pages))
+				pgm->code = PGM_ADDRESSING;
+		}
+		if (pgm->code)
+			return pgm->code;
+		ga += PAGE_SIZE;
+		pages++;
+		nr_pages--;
+	}
+	return 0;
+}
+
+int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data,
+		 unsigned long len, int write)
+{
+	psw_t *psw = &vcpu->arch.sie_block->gpsw;
+	unsigned long _len, nr_pages, gpa, idx;
+	unsigned long pages_array[2];
+	unsigned long *pages;
+	int rc;
+
+	if (!len)
+		return 0;
+	/* Access register mode is not supported yet. */
+	if (psw_bits(*psw).t && psw_bits(*psw).as == PSW_AS_ACCREG)
+		return -EOPNOTSUPP;
+	nr_pages = (((ga & ~PAGE_MASK) + len - 1) >> PAGE_SHIFT) + 1;
+	pages = pages_array;
+	if (nr_pages > ARRAY_SIZE(pages_array))
+		pages = vmalloc(nr_pages * sizeof(unsigned long));
+	if (!pages)
+		return -ENOMEM;
+	rc = guest_page_range(vcpu, ga, pages, nr_pages, write);
+	for (idx = 0; idx < nr_pages && !rc; idx++) {
+		gpa = *(pages + idx) + (ga & ~PAGE_MASK);
+		_len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len);
+		if (write)
+			rc = kvm_write_guest(vcpu->kvm, gpa, data, _len);
+		else
+			rc = kvm_read_guest(vcpu->kvm, gpa, data, _len);
+		len -= _len;
+		ga += _len;
+		data += _len;
+	}
+	if (nr_pages > ARRAY_SIZE(pages_array))
+		vfree(pages);
+	return rc;
+}
+
+int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra,
+		      void *data, unsigned long len, int write)
+{
+	unsigned long _len, gpa;
+	int rc = 0;
+
+	while (len && !rc) {
+		gpa = kvm_s390_real_to_abs(vcpu, gra);
+		_len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len);
+		if (write)
+			rc = write_guest_abs(vcpu, gpa, data, _len);
+		else
+			rc = read_guest_abs(vcpu, gpa, data, _len);
+		len -= _len;
+		gra += _len;
+		data += _len;
+	}
+	return rc;
+}
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index 917aeaa04fff..21ee62cd948e 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -227,4 +227,174 @@ int read_guest_lc(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
 
 	return kvm_read_guest(vcpu->kvm, gpa, data, len);
 }
+
+int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data,
+		 unsigned long len, int write);
+
+int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra,
+		      void *data, unsigned long len, int write);
+
+/**
+ * write_guest - copy data from kernel space to guest space
+ * @vcpu: virtual cpu
+ * @ga: guest address
+ * @data: source address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @data (kernel space) to @ga (guest address).
+ * In order to copy data to guest space the PSW of the vcpu is inspected:
+ * If DAT is off data will be copied to guest real or absolute memory.
+ * If DAT is on data will be copied to the address space as specified by
+ * the address space bits of the PSW:
+ * Primary, secondory or home space (access register mode is currently not
+ * implemented).
+ * The addressing mode of the PSW is also inspected, so that address wrap
+ * around is taken into account for 24-, 31- and 64-bit addressing mode,
+ * if the to be copied data crosses page boundaries in guest address space.
+ * In addition also low address and DAT protection are inspected before
+ * copying any data (key protection is currently not implemented).
+ *
+ * This function modifies the 'struct kvm_s390_pgm_info pgm' member of @vcpu.
+ * In case of an access exception (e.g. protection exception) pgm will contain
+ * all data necessary so that a subsequent call to 'kvm_s390_inject_prog_vcpu()'
+ * will inject a correct exception into the guest.
+ * If no access exception happened, the contents of pgm are undefined when
+ * this function returns.
+ *
+ * Returns:  - zero on success
+ *	     - a negative value if e.g. the guest mapping is broken or in
+ *	       case of out-of-memory. In this case the contents of pgm are
+ *	       undefined. Also parts of @data may have been copied to guest
+ *	       space.
+ *	     - a positive value if an access exception happened. In this case
+ *	       the returned value is the program interruption code and the
+ *	       contents of pgm may be used to inject an exception into the
+ *	       guest. No data has been copied to guest space.
+ *
+ * Note: in case an access exception is recognized no data has been copied to
+ *	 guest space (this is also true, if the to be copied data would cross
+ *	 one or more page boundaries in guest space).
+ *	 Therefore this function may be used for nullifying and suppressing
+ *	 instruction emulation.
+ *	 It may also be used for terminating instructions, if it is undefined
+ *	 if data has been changed in guest space in case of an exception.
+ */
+static inline __must_check
+int write_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data,
+		unsigned long len)
+{
+	return access_guest(vcpu, ga, data, len, 1);
+}
+
+/**
+ * read_guest - copy data from guest space to kernel space
+ * @vcpu: virtual cpu
+ * @ga: guest address
+ * @data: destination address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @ga (guest address) to @data (kernel space).
+ *
+ * The behaviour of read_guest is identical to write_guest, except that
+ * data will be copied from guest space to kernel space.
+ */
+static inline __must_check
+int read_guest(struct kvm_vcpu *vcpu, unsigned long ga, void *data,
+	       unsigned long len)
+{
+	return access_guest(vcpu, ga, data, len, 0);
+}
+
+/**
+ * write_guest_abs - copy data from kernel space to guest space absolute
+ * @vcpu: virtual cpu
+ * @gpa: guest physical (absolute) address
+ * @data: source address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @data (kernel space) to @gpa (guest absolute address).
+ * It is up to the caller to ensure that the entire guest memory range is
+ * valid memory before calling this function.
+ * Guest low address and key protection are not checked.
+ *
+ * Returns zero on success or -EFAULT on error.
+ *
+ * If an error occurs data may have been copied partially to guest memory.
+ */
+static inline __must_check
+int write_guest_abs(struct kvm_vcpu *vcpu, unsigned long gpa, void *data,
+		    unsigned long len)
+{
+	return kvm_write_guest(vcpu->kvm, gpa, data, len);
+}
+
+/**
+ * read_guest_abs - copy data from guest space absolute to kernel space
+ * @vcpu: virtual cpu
+ * @gpa: guest physical (absolute) address
+ * @data: destination address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @gpa (guest absolute address) to @data (kernel space).
+ * It is up to the caller to ensure that the entire guest memory range is
+ * valid memory before calling this function.
+ * Guest key protection is not checked.
+ *
+ * Returns zero on success or -EFAULT on error.
+ *
+ * If an error occurs data may have been copied partially to kernel space.
+ */
+static inline __must_check
+int read_guest_abs(struct kvm_vcpu *vcpu, unsigned long gpa, void *data,
+		   unsigned long len)
+{
+	return kvm_read_guest(vcpu->kvm, gpa, data, len);
+}
+
+/**
+ * write_guest_real - copy data from kernel space to guest space real
+ * @vcpu: virtual cpu
+ * @gra: guest real address
+ * @data: source address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @data (kernel space) to @gra (guest real address).
+ * It is up to the caller to ensure that the entire guest memory range is
+ * valid memory before calling this function.
+ * Guest low address and key protection are not checked.
+ *
+ * Returns zero on success or -EFAULT on error.
+ *
+ * If an error occurs data may have been copied partially to guest memory.
+ */
+static inline __must_check
+int write_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
+		     unsigned long len)
+{
+	return access_guest_real(vcpu, gra, data, len, 1);
+}
+
+/**
+ * read_guest_real - copy data from guest space real to kernel space
+ * @vcpu: virtual cpu
+ * @gra: guest real address
+ * @data: destination address in kernel space
+ * @len: number of bytes to copy
+ *
+ * Copy @len bytes from @gra (guest real address) to @data (kernel space).
+ * It is up to the caller to ensure that the entire guest memory range is
+ * valid memory before calling this function.
+ * Guest key protection is not checked.
+ *
+ * Returns zero on success or -EFAULT on error.
+ *
+ * If an error occurs data may have been copied partially to kernel space.
+ */
+static inline __must_check
+int read_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, void *data,
+		    unsigned long len)
+{
+	return access_guest_real(vcpu, gra, data, len, 0);
+}
+
 #endif /* __KVM_S390_GACCESS_H */