5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
[ Upstream commit bad13799e0305deb258372b7298a86be4c78aaba ]
Introduce a helper function for guest frame access.
Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
Message-Id: <20211126164549.7046-4-scgl@xxxxxxxxxxxxx>
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
Stable-dep-of: e8061f06185b ("KVM: s390: gaccess: Check if guest address is in memslot")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/s390/kvm/gaccess.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index ca7f22a9e0c57..4460808c3b9a0 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -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;
--
2.43.0
