linux-kernel - [PATCH v6 11/14] KVM: s390: Refactor absolute vcpu mem

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Date:   Wed, 25 Jan 2023 22:26:05 +0100
From:   Janis Schoetterl-Glausch <scgl@...ux.ibm.com>
To:     Christian Borntraeger <borntraeger@...ux.ibm.com>,
        Janosch Frank <frankja@...ux.ibm.com>,
        Claudio Imbrenda <imbrenda@...ux.ibm.com>,
        Heiko Carstens <hca@...ux.ibm.com>,
        Vasily Gorbik <gor@...ux.ibm.com>,
        Alexander Gordeev <agordeev@...ux.ibm.com>
Cc:     Janis Schoetterl-Glausch <scgl@...ux.ibm.com>,
        David Hildenbrand <david@...hat.com>,
        Jonathan Corbet <corbet@....net>, kvm@...r.kernel.org,
        linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-kselftest@...r.kernel.org, linux-s390@...r.kernel.org,
        Paolo Bonzini <pbonzini@...hat.com>,
        Shuah Khan <shuah@...nel.org>,
        Sven Schnelle <svens@...ux.ibm.com>
Subject: [PATCH v6 11/14] KVM: s390: Refactor absolute vcpu mem_op function

Remove code duplication with regards to the CHECK_ONLY flag.
Decrease the number of indents.
No functional change indented.

Suggested-by: Janosch Frank <frankja@...ux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@...ux.ibm.com>
---


Cosmetic only, can be dropped.


 arch/s390/kvm/kvm-s390.c | 34 +++++++++++++++-------------------
 1 file changed, 15 insertions(+), 19 deletions(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index cfd09cb43ef6..4b8b41be7aed 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -5262,6 +5262,7 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu,
 				 struct kvm_s390_mem_op *mop)
 {
 	void __user *uaddr = (void __user *)mop->buf;
+	enum gacc_mode acc_mode;
 	void *tmpbuf = NULL;
 	int r;
 
@@ -5278,38 +5279,33 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu,
 	if (IS_ERR(tmpbuf))
 		return PTR_ERR(tmpbuf);
 
-	switch (mop->op) {
-	case KVM_S390_MEMOP_LOGICAL_READ:
-		if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) {
-			r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size,
-					    GACC_FETCH, mop->key);
-			break;
-		}
+	acc_mode = mop->op == KVM_S390_MEMOP_LOGICAL_READ ? GACC_FETCH : GACC_STORE;
+	if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) {
+		r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size,
+				    acc_mode, mop->key);
+	} else if (acc_mode == GACC_FETCH) {
 		r = read_guest_with_key(vcpu, mop->gaddr, mop->ar, tmpbuf,
 					mop->size, mop->key);
-		if (r == 0) {
-			if (copy_to_user(uaddr, tmpbuf, mop->size))
-				r = -EFAULT;
-		}
-		break;
-	case KVM_S390_MEMOP_LOGICAL_WRITE:
-		if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) {
-			r = check_gva_range(vcpu, mop->gaddr, mop->ar, mop->size,
-					    GACC_STORE, mop->key);
-			break;
+		if (r)
+			goto out_inject;
+		if (copy_to_user(uaddr, tmpbuf, mop->size)) {
+			r = -EFAULT;
+			goto out_free;
 		}
+	} else {
 		if (copy_from_user(tmpbuf, uaddr, mop->size)) {
 			r = -EFAULT;
-			break;
+			goto out_free;
 		}
 		r = write_guest_with_key(vcpu, mop->gaddr, mop->ar, tmpbuf,
 					 mop->size, mop->key);
-		break;
 	}
 
+out_inject:
 	if (r > 0 && (mop->flags & KVM_S390_MEMOP_F_INJECT_EXCEPTION) != 0)
 		kvm_s390_inject_prog_irq(vcpu, &vcpu->arch.pgm);
 
+out_free:
 	vfree(tmpbuf);
 	return r;
 }
-- 
2.34.1