KVM: s390: Refactor 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@linux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-12-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-12-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 23f50437a328df36d1ddd02bf961d7bc9d83bebc..17368d118653971d82b78defc0d2af24b259d517 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -5254,6 +5254,7 @@ 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;
 
@@ -5272,38 +5273,35 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu,
                        return -ENOMEM;
        }
 
-       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);
+               goto out_inject;
+       }
+       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;
 }