The vcpu and vm mem_op ioctl implementations share some functionality. Move argument checking and buffer allocation into functions and call them from both implementations. This allows code reuse in case of additional future mem_op operations.
Suggested-by: Janosch Frank frankja@linux.ibm.com Signed-off-by: Janis Schoetterl-Glausch scgl@linux.ibm.com --- arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- 1 file changed, 42 insertions(+), 38 deletions(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index e4890e04b210..e0dfaa195949 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) return r; }
-static bool access_key_invalid(u8 access_key) +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) { - return access_key > 0xf; + if (mop->flags & ~supported_flags || !mop->size) + return -EINVAL; + if (mop->size > MEM_OP_MAX_SIZE) + return -E2BIG; + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { + if (mop->key > 0xf) + return -EINVAL; + } else { + mop->key = 0; + } + return 0; +} + +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) +{ + void *buf; + + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) + return NULL; + buf = vmalloc(mop->size); + if (!buf) + return ERR_PTR(-ENOMEM); + return buf; }
static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; - u64 supported_flags; void *tmpbuf = NULL; int r, srcu_idx;
- supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION - | KVM_S390_MEMOP_F_CHECK_ONLY; - if (mop->flags & ~supported_flags || !mop->size) - return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) - return -E2BIG; + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | + KVM_S390_MEMOP_F_CHECK_ONLY); + if (r) + return r; + /* * This is technically a heuristic only, if the kvm->lock is not * taken, it is not guaranteed that the vm is/remains non-protected. @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) */ if (kvm_s390_pv_get_handle(kvm)) return -EINVAL; - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { - if (access_key_invalid(mop->key)) - return -EINVAL; - } else { - mop->key = 0; - } - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { - tmpbuf = vmalloc(mop->size); - if (!tmpbuf) - return -ENOMEM; - } + tmpbuf = mem_op_alloc_buf(mop); + if (IS_ERR(tmpbuf)) + return PTR_ERR(tmpbuf);
srcu_idx = srcu_read_lock(&kvm->srcu);
@@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, { void __user *uaddr = (void __user *)mop->buf; void *tmpbuf = NULL; - int r = 0; - const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION - | KVM_S390_MEMOP_F_CHECK_ONLY - | KVM_S390_MEMOP_F_SKEY_PROTECTION; + int r;
- if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_INJECT_EXCEPTION | + KVM_S390_MEMOP_F_CHECK_ONLY | + KVM_S390_MEMOP_F_SKEY_PROTECTION); + if (r) + return r; + if (mop->ar >= NUM_ACRS) return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) - return -E2BIG; if (kvm_s390_pv_cpu_is_protected(vcpu)) return -EINVAL; - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { - if (access_key_invalid(mop->key)) - return -EINVAL; - } else { - mop->key = 0; - } - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { - tmpbuf = vmalloc(mop->size); - if (!tmpbuf) - return -ENOMEM; - } + tmpbuf = mem_op_alloc_buf(mop); + if (IS_ERR(tmpbuf)) + return PTR_ERR(tmpbuf);
switch (mop->op) { case KVM_S390_MEMOP_LOGICAL_READ: