Commit a41f505e authored by Janis Schoetterl-Glausch's avatar Janis Schoetterl-Glausch Committed by Janosch Frank
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KVM: s390: Move common code of mem_op functions into function 



The vcpu and vm mem_op ioctl implementations share some functionality.
Move argument checking into a function and call it from both
implementations. This allows code reuse in case of additional future
mem_op operations.

Suggested-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Signed-off-by: default avatarJanis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: default avatarJanosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-9-scgl@linux.ibm.com


Message-Id: <20230206164602.138068-9-scgl@linux.ibm.com>
Signed-off-by: default avatarJanosch Frank <frankja@linux.ibm.com>
parent dc55ceae

arch/s390/kvm/kvm-s390.c

+24 −28
Original line number Diff line number Diff line
@@ -2764,24 +2764,32 @@ 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 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.
@@ -2793,12 +2801,6 @@ 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)
@@ -5250,23 +5252,17 @@ 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)