static int __must_check __deliver_prog()

in kvm/interrupt.c [854:971]

• 109 lines of code
• 39 McCabe index (conditional complexity)

static int __must_check __deliver_prog(struct kvm_vcpu *vcpu)
{
	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
	struct kvm_s390_pgm_info pgm_info;
	int rc = 0, nullifying = false;
	u16 ilen;

	spin_lock(&li->lock);
	pgm_info = li->irq.pgm;
	clear_bit(IRQ_PEND_PROG, &li->pending_irqs);
	memset(&li->irq.pgm, 0, sizeof(pgm_info));
	spin_unlock(&li->lock);

	ilen = pgm_info.flags & KVM_S390_PGM_FLAGS_ILC_MASK;
	VCPU_EVENT(vcpu, 3, "deliver: program irq code 0x%x, ilen:%d",
		   pgm_info.code, ilen);
	vcpu->stat.deliver_program++;
	trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_PROGRAM_INT,
					 pgm_info.code, 0);

	/* PER is handled by the ultravisor */
	if (kvm_s390_pv_cpu_is_protected(vcpu))
		return __deliver_prog_pv(vcpu, pgm_info.code & ~PGM_PER);

	switch (pgm_info.code & ~PGM_PER) {
	case PGM_AFX_TRANSLATION:
	case PGM_ASX_TRANSLATION:
	case PGM_EX_TRANSLATION:
	case PGM_LFX_TRANSLATION:
	case PGM_LSTE_SEQUENCE:
	case PGM_LSX_TRANSLATION:
	case PGM_LX_TRANSLATION:
	case PGM_PRIMARY_AUTHORITY:
	case PGM_SECONDARY_AUTHORITY:
		nullifying = true;
		fallthrough;
	case PGM_SPACE_SWITCH:
		rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
				  (u64 *)__LC_TRANS_EXC_CODE);
		break;
	case PGM_ALEN_TRANSLATION:
	case PGM_ALE_SEQUENCE:
	case PGM_ASTE_INSTANCE:
	case PGM_ASTE_SEQUENCE:
	case PGM_ASTE_VALIDITY:
	case PGM_EXTENDED_AUTHORITY:
		rc = put_guest_lc(vcpu, pgm_info.exc_access_id,
				  (u8 *)__LC_EXC_ACCESS_ID);
		nullifying = true;
		break;
	case PGM_ASCE_TYPE:
	case PGM_PAGE_TRANSLATION:
	case PGM_REGION_FIRST_TRANS:
	case PGM_REGION_SECOND_TRANS:
	case PGM_REGION_THIRD_TRANS:
	case PGM_SEGMENT_TRANSLATION:
		rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
				  (u64 *)__LC_TRANS_EXC_CODE);
		rc |= put_guest_lc(vcpu, pgm_info.exc_access_id,
				   (u8 *)__LC_EXC_ACCESS_ID);
		rc |= put_guest_lc(vcpu, pgm_info.op_access_id,
				   (u8 *)__LC_OP_ACCESS_ID);
		nullifying = true;
		break;
	case PGM_MONITOR:
		rc = put_guest_lc(vcpu, pgm_info.mon_class_nr,
				  (u16 *)__LC_MON_CLASS_NR);
		rc |= put_guest_lc(vcpu, pgm_info.mon_code,
				   (u64 *)__LC_MON_CODE);
		break;
	case PGM_VECTOR_PROCESSING:
	case PGM_DATA:
		rc = put_guest_lc(vcpu, pgm_info.data_exc_code,
				  (u32 *)__LC_DATA_EXC_CODE);
		break;
	case PGM_PROTECTION:
		rc = put_guest_lc(vcpu, pgm_info.trans_exc_code,
				  (u64 *)__LC_TRANS_EXC_CODE);
		rc |= put_guest_lc(vcpu, pgm_info.exc_access_id,
				   (u8 *)__LC_EXC_ACCESS_ID);
		break;
	case PGM_STACK_FULL:
	case PGM_STACK_EMPTY:
	case PGM_STACK_SPECIFICATION:
	case PGM_STACK_TYPE:
	case PGM_STACK_OPERATION:
	case PGM_TRACE_TABEL:
	case PGM_CRYPTO_OPERATION:
		nullifying = true;
		break;
	}

	if (pgm_info.code & PGM_PER) {
		rc |= put_guest_lc(vcpu, pgm_info.per_code,
				   (u8 *) __LC_PER_CODE);
		rc |= put_guest_lc(vcpu, pgm_info.per_atmid,
				   (u8 *)__LC_PER_ATMID);
		rc |= put_guest_lc(vcpu, pgm_info.per_address,
				   (u64 *) __LC_PER_ADDRESS);
		rc |= put_guest_lc(vcpu, pgm_info.per_access_id,
				   (u8 *) __LC_PER_ACCESS_ID);
	}

	if (nullifying && !(pgm_info.flags & KVM_S390_PGM_FLAGS_NO_REWIND))
		kvm_s390_rewind_psw(vcpu, ilen);

	/* bit 1+2 of the target are the ilc, so we can directly use ilen */
	rc |= put_guest_lc(vcpu, ilen, (u16 *) __LC_PGM_ILC);
	rc |= put_guest_lc(vcpu, vcpu->arch.sie_block->gbea,
				 (u64 *) __LC_PGM_LAST_BREAK);
	rc |= put_guest_lc(vcpu, pgm_info.code,
			   (u16 *)__LC_PGM_INT_CODE);
	rc |= write_guest_lc(vcpu, __LC_PGM_OLD_PSW,
			     &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
	rc |= read_guest_lc(vcpu, __LC_PGM_NEW_PSW,
			    &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
	return rc ? -EFAULT : 0;
}