Commit bad13799 authored by Janis Schoetterl-Glausch's avatar Janis Schoetterl-Glausch Committed by Janosch Frank
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KVM: s390: gaccess: Cleanup access to guest pages 



Introduce a helper function for guest frame access.

Signed-off-by: default avatarJanis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarClaudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20211126164549.7046-4-scgl@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
parent 7faa543d

arch/s390/kvm/gaccess.c

+16 −8
Original line number Diff line number Diff line
@@ -866,6 +866,20 @@ static int guest_range_to_gpas(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, 
	return 0;

}



static int access_guest_page(struct kvm *kvm, enum gacc_mode mode, gpa_t gpa,

			     void *data, unsigned int len)

{

	const unsigned int offset = offset_in_page(gpa);

	const gfn_t gfn = gpa_to_gfn(gpa);

	int rc;



	if (mode == GACC_STORE)

		rc = kvm_write_guest_page(kvm, gfn, data, offset, len);

	else

		rc = kvm_read_guest_page(kvm, gfn, data, offset, len);

	return rc;

}



int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data,

		 unsigned long len, enum gacc_mode mode)

{
@@ -896,10 +910,7 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data, 
	rc = guest_range_to_gpas(vcpu, ga, ar, gpas, len, asce, mode);

	for (idx = 0; idx < nr_pages && !rc; idx++) {

		fragment_len = min(PAGE_SIZE - offset_in_page(gpas[idx]), len);

		if (mode == GACC_STORE)

			rc = kvm_write_guest(vcpu->kvm, gpas[idx], data, fragment_len);

		else

			rc = kvm_read_guest(vcpu->kvm, gpas[idx], data, fragment_len);

		rc = access_guest_page(vcpu->kvm, mode, gpas[idx], data, fragment_len);

		len -= fragment_len;

		data += fragment_len;

	}
@@ -920,10 +931,7 @@ int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra, 
	while (len && !rc) {

		gpa = kvm_s390_real_to_abs(vcpu, gra);

		fragment_len = min(PAGE_SIZE - offset_in_page(gpa), len);

		if (mode)

			rc = write_guest_abs(vcpu, gpa, data, fragment_len);

		else

			rc = read_guest_abs(vcpu, gpa, data, fragment_len);

		rc = access_guest_page(vcpu->kvm, mode, gpa, data, fragment_len);

		len -= fragment_len;

		gra += fragment_len;

		data += fragment_len;