Exemple #1
0
void benchmark_track_utilisation_dump(void)
{
    uint64_t *buffer = ((uint64_t *) & (((seL4_IPCBuffer *)lookupIPCBuffer(true, NODE_STATE(ksCurThread)))->msg[0]));
    tcb_t *tcb = NULL;
    word_t tcb_cptr = getRegister(NODE_STATE(ksCurThread), capRegister);
    lookupCap_ret_t lu_ret;
    word_t cap_type;

    lu_ret = lookupCap(NODE_STATE(ksCurThread), tcb_cptr);
    /* ensure we got a TCB cap */
    cap_type = cap_get_capType(lu_ret.cap);
    if (cap_type != cap_thread_cap) {
        userError("SysBenchmarkFinalizeLog: cap is not a TCB, halting");
        return;
    }

    tcb = TCB_PTR(cap_thread_cap_get_capTCBPtr(lu_ret.cap));
    buffer[BENCHMARK_TCB_UTILISATION] = tcb->benchmark.utilisation; /* Requested thread utilisation */
    buffer[BENCHMARK_IDLE_LOCALCPU_UTILISATION] = NODE_STATE(
                                                      ksIdleThread)->benchmark.utilisation; /* Idle thread utilisation of current CPU */
#ifdef ENABLE_SMP_SUPPORT
    buffer[BENCHMARK_IDLE_TCBCPU_UTILISATION] = NODE_STATE_ON_CORE(ksIdleThread,
                                                                   tcb->tcbAffinity)->benchmark.utilisation; /* Idle thread utilisation of CPU the TCB is running on */
#else
    buffer[BENCHMARK_IDLE_TCBCPU_UTILISATION] = buffer[BENCHMARK_IDLE_LOCALCPU_UTILISATION];
#endif

#ifdef CONFIG_ARM_ENABLE_PMU_OVERFLOW_INTERRUPT
    buffer[BENCHMARK_TOTAL_UTILISATION] =
        (ccnt_num_overflows * 0xFFFFFFFFU) + benchmark_end_time - benchmark_start_time;
#else
    buffer[BENCHMARK_TOTAL_UTILISATION] = benchmark_end_time - benchmark_start_time; /* Overall time */
#endif /* CONFIG_ARM_ENABLE_PMU_OVERFLOW_INTERRUPT */

}
Exemple #2
0
exception_t
handleUserLevelDebugException(int int_vector)
{
    tcb_t *ct;
    getAndResetActiveBreakpoint_t active_bp;
    testAndResetSingleStepException_t single_step_info;

#if defined(CONFIG_DEBUG_BUILD) || defined(CONFIG_BENCHMARK_TRACK_KERNEL_ENTRIES)
    ksKernelEntry.path = Entry_UserLevelFault;
    ksKernelEntry.word = int_vector;
#else
    (void)int_vector;
#endif /* DEBUG */

#ifdef CONFIG_BENCHMARK_TRACK_KERNEL_ENTRIES
    benchmark_track_start();
#endif

    ct = NODE_STATE(ksCurThread);

    /* Software break request (INT3) is detected by the vector number */
    if (int_vector == int_software_break_request) {
        current_fault = seL4_Fault_DebugException_new(getRestartPC(NODE_STATE(ksCurThread)),
                                                      0, seL4_SoftwareBreakRequest);
    } else {
        /* Hardware breakpoint trigger is detected using DR6 */
        active_bp = getAndResetActiveBreakpoint(ct);
        if (active_bp.bp_num >= 0) {
            current_fault = seL4_Fault_DebugException_new(active_bp.vaddr,
                                                          active_bp.bp_num,
                                                          active_bp.reason);
        } else {
            single_step_info = testAndResetSingleStepException(ct);
            if (single_step_info.ret == true) {
                /* If the caller asked us to skip over N instructions before
                 * generating the next single-step breakpoint, we shouldn't
                 * bother to construct a fault message until we've skipped N
                 * instructions.
                 */
                if (singleStepFaultCounterReady(ct) == false) {
                    return EXCEPTION_NONE;
                }
                current_fault = seL4_Fault_DebugException_new(single_step_info.instr_vaddr,
                                                              0, seL4_SingleStep);
            } else {
                return EXCEPTION_SYSCALL_ERROR;
            }
        }
    }

    handleFault(NODE_STATE(ksCurThread));

    schedule();
    activateThread();

    return EXCEPTION_NONE;
}
Exemple #3
0
exception_t
decodeIRQHandlerInvocation(word_t invLabel, irq_t irq,
                           extra_caps_t excaps)
{
    switch (invLabel) {
    case IRQAckIRQ:
        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        invokeIRQHandler_AckIRQ(irq);
        return EXCEPTION_NONE;

    case IRQSetIRQHandler: {
        cap_t ntfnCap;
        cte_t *slot;

        if (excaps.excaprefs[0] == NULL) {
            current_syscall_error.type = seL4_TruncatedMessage;
            return EXCEPTION_SYSCALL_ERROR;
        }
        ntfnCap = excaps.excaprefs[0]->cap;
        slot = excaps.excaprefs[0];

        if (cap_get_capType(ntfnCap) != cap_notification_cap ||
                !cap_notification_cap_get_capNtfnCanSend(ntfnCap)) {
            if (cap_get_capType(ntfnCap) != cap_notification_cap) {
                userError("IRQSetHandler: provided cap is not an notification capability.");
            } else {
                userError("IRQSetHandler: caller does not have send rights on the endpoint.");
            }
            current_syscall_error.type = seL4_InvalidCapability;
            current_syscall_error.invalidCapNumber = 0;
            return EXCEPTION_SYSCALL_ERROR;
        }

        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        invokeIRQHandler_SetIRQHandler(irq, ntfnCap, slot);
        return EXCEPTION_NONE;
    }

    case IRQClearIRQHandler:
        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        invokeIRQHandler_ClearIRQHandler(irq);
        return EXCEPTION_NONE;

    default:
        userError("IRQHandler: Illegal operation.");
        current_syscall_error.type = seL4_IllegalOperation;
        return EXCEPTION_SYSCALL_ERROR;
    }
}
Exemple #4
0
static void sendRunqueues(void)
{
    word_t i;
    sendWord((unsigned long)NODE_STATE(ksCurThread));
    for (i = 0; i < NUM_READY_QUEUES; i++) {
        tcb_t *current = NODE_STATE(ksReadyQueues[i]).head;
        if (current != 0) {
            while (current != NODE_STATE(ksReadyQueues[i]).end) {
                sendWord((unsigned long)current);
                current = current -> tcbSchedNext;
            }
            sendWord((unsigned long)current);
        }
    }
}
Exemple #5
0
exception_t
decodeIRQControlInvocation(word_t invLabel, word_t length,
                           cte_t *srcSlot, extra_caps_t excaps,
                           word_t *buffer)
{
    if (invLabel == IRQIssueIRQHandler) {
        word_t index, depth, irq_w;
        irq_t irq;
        cte_t *destSlot;
        cap_t cnodeCap;
        lookupSlot_ret_t lu_ret;
        exception_t status;

        if (length < 3 || excaps.excaprefs[0] == NULL) {
            current_syscall_error.type = seL4_TruncatedMessage;
            return EXCEPTION_SYSCALL_ERROR;
        }
        irq_w = getSyscallArg(0, buffer);
        irq = (irq_t) irq_w;
        index = getSyscallArg(1, buffer);
        depth = getSyscallArg(2, buffer);

        cnodeCap = excaps.excaprefs[0]->cap;

        status = Arch_checkIRQ(irq);
        if (status != EXCEPTION_NONE) {
            return status;
        }

        if (isIRQActive(irq)) {
            current_syscall_error.type = seL4_RevokeFirst;
            userError("Rejecting request for IRQ %u. Already active.", (int)irq);
            return EXCEPTION_SYSCALL_ERROR;
        }

        lu_ret = lookupTargetSlot(cnodeCap, index, depth);
        if (lu_ret.status != EXCEPTION_NONE) {
            userError("Target slot for new IRQ Handler cap invalid: cap %lu, IRQ %u.",
                      getExtraCPtr(buffer, 0), (int)irq);
            return lu_ret.status;
        }
        destSlot = lu_ret.slot;

        status = ensureEmptySlot(destSlot);
        if (status != EXCEPTION_NONE) {
            userError("Target slot for new IRQ Handler cap not empty: cap %lu, IRQ %u.",
                      getExtraCPtr(buffer, 0), (int)irq);
            return status;
        }

        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        return invokeIRQControl(irq, destSlot, srcSlot);
    } else {
        return Arch_decodeIRQControlInvocation(invLabel, length, srcSlot, excaps, buffer);
    }
}
Exemple #6
0
void benchmark_track_reset_utilisation(void)
{
    tcb_t *tcb = NULL;
    word_t tcb_cptr = getRegister(NODE_STATE(ksCurThread), capRegister);
    lookupCap_ret_t lu_ret;
    word_t cap_type;

    lu_ret = lookupCap(NODE_STATE(ksCurThread), tcb_cptr);
    /* ensure we got a TCB cap */
    cap_type = cap_get_capType(lu_ret.cap);
    if (cap_type != cap_thread_cap) {
        userError("SysBenchmarkResetThreadUtilisation: cap is not a TCB, halting");
        return;
    }

    tcb = TCB_PTR(cap_thread_cap_get_capTCBPtr(lu_ret.cap));

    tcb->benchmark.utilisation = 0;
    tcb->benchmark.schedule_start_time = 0;
}
Exemple #7
0
void fastpath_reply_recv(word_t cptr, word_t msgInfo)
{
    seL4_MessageInfo_t info;
    cap_t ep_cap;
    endpoint_t *ep_ptr;
    word_t length;
    cte_t *callerSlot;
    cap_t callerCap;
    tcb_t *caller;
    word_t badge;
    tcb_t *endpointTail;
    word_t fault_type;

    cap_t newVTable;
    vspace_root_t *cap_pd;
    pde_t stored_hw_asid;
    dom_t dom;

    /* Get message info and length */
    info = messageInfoFromWord_raw(msgInfo);
    length = seL4_MessageInfo_get_length(info);
    fault_type = seL4_Fault_get_seL4_FaultType(NODE_STATE(ksCurThread)->tcbFault);

    /* Check there's no extra caps, the length is ok and there's no
     * saved fault. */
    if (unlikely(fastpath_mi_check(msgInfo) ||
                 fault_type != seL4_Fault_NullFault)) {
        slowpath(SysReplyRecv);
    }

    /* Lookup the cap */
    ep_cap = lookup_fp(TCB_PTR_CTE_PTR(NODE_STATE(ksCurThread), tcbCTable)->cap,
                       cptr);

    /* Check it's an endpoint */
    if (unlikely(!cap_capType_equals(ep_cap, cap_endpoint_cap) ||
                 !cap_endpoint_cap_get_capCanReceive(ep_cap))) {
        slowpath(SysReplyRecv);
    }

    /* Check there is nothing waiting on the notification */
    if (NODE_STATE(ksCurThread)->tcbBoundNotification &&
        notification_ptr_get_state(NODE_STATE(ksCurThread)->tcbBoundNotification) == NtfnState_Active) {
        slowpath(SysReplyRecv);
    }

    /* Get the endpoint address */
    ep_ptr = EP_PTR(cap_endpoint_cap_get_capEPPtr(ep_cap));

    /* Check that there's not a thread waiting to send */
    if (unlikely(endpoint_ptr_get_state(ep_ptr) == EPState_Send)) {
        slowpath(SysReplyRecv);
    }

    /* Only reply if the reply cap is valid. */
    callerSlot = TCB_PTR_CTE_PTR(NODE_STATE(ksCurThread), tcbCaller);
    callerCap = callerSlot->cap;
    if (unlikely(!fastpath_reply_cap_check(callerCap))) {
        slowpath(SysReplyRecv);
    }

    /* Determine who the caller is. */
    caller = TCB_PTR(cap_reply_cap_get_capTCBPtr(callerCap));

    /* ensure we are not single stepping the caller in ia32 */
#if defined(CONFIG_HARDWARE_DEBUG_API) && defined(CONFIG_ARCH_IA32)
    if (caller->tcbArch.tcbContext.breakpointState.single_step_enabled) {
        slowpath(SysReplyRecv);
    }
#endif

    /* Check that the caller has not faulted, in which case a fault
       reply is generated instead. */
    fault_type = seL4_Fault_get_seL4_FaultType(caller->tcbFault);
    if (unlikely(fault_type != seL4_Fault_NullFault)) {
        slowpath(SysReplyRecv);
    }

    /* Get destination thread.*/
    newVTable = TCB_PTR_CTE_PTR(caller, tcbVTable)->cap;

    /* Get vspace root. */
    cap_pd = cap_vtable_cap_get_vspace_root_fp(newVTable);

    /* Ensure that the destination has a valid MMU. */
    if (unlikely(! isValidVTableRoot_fp(newVTable))) {
        slowpath(SysReplyRecv);
    }

#ifdef CONFIG_ARCH_AARCH32
    /* Get HWASID. */
    stored_hw_asid = cap_pd[PD_ASID_SLOT];
#endif

#ifdef CONFIG_ARCH_X86_64
    stored_hw_asid.words[0] = cap_pml4_cap_get_capPML4MappedASID(newVTable);
#endif

#ifdef CONFIG_ARCH_AARCH64
    stored_hw_asid.words[0] = cap_page_global_directory_cap_get_capPGDMappedASID(newVTable);
#endif

#ifdef CONFIG_ARCH_RISCV
    stored_hw_asid.words[0] = cap_page_table_cap_get_capPTMappedASID(newVTable);
#endif

    /* Ensure the original caller can be scheduled directly. */
    dom = maxDom ? ksCurDomain : 0;
    if (unlikely(!isHighestPrio(dom, caller->tcbPriority))) {
        slowpath(SysReplyRecv);
    }

#ifdef CONFIG_ARCH_AARCH32
    /* Ensure the HWASID is valid. */
    if (unlikely(!pde_pde_invalid_get_stored_asid_valid(stored_hw_asid))) {
        slowpath(SysReplyRecv);
    }
#endif

    /* Ensure the original caller is in the current domain and can be scheduled directly. */
    if (unlikely(caller->tcbDomain != ksCurDomain && maxDom)) {
        slowpath(SysReplyRecv);
    }

#ifdef ENABLE_SMP_SUPPORT
    /* Ensure both threads have the same affinity */
    if (unlikely(NODE_STATE(ksCurThread)->tcbAffinity != caller->tcbAffinity)) {
        slowpath(SysReplyRecv);
    }
#endif /* ENABLE_SMP_SUPPORT */

    /*
     * --- POINT OF NO RETURN ---
     *
     * At this stage, we have committed to performing the IPC.
     */

#ifdef CONFIG_BENCHMARK_TRACK_KERNEL_ENTRIES
    ksKernelEntry.is_fastpath = true;
#endif

    /* Set thread state to BlockedOnReceive */
    thread_state_ptr_mset_blockingObject_tsType(
        &NODE_STATE(ksCurThread)->tcbState, (word_t)ep_ptr, ThreadState_BlockedOnReceive);
    thread_state_ptr_set_blockingIPCCanGrant(&NODE_STATE(ksCurThread)->tcbState,
                                             cap_endpoint_cap_get_capCanGrant(ep_cap));;

    /* Place the thread in the endpoint queue */
    endpointTail = endpoint_ptr_get_epQueue_tail_fp(ep_ptr);
    if (likely(!endpointTail)) {
        NODE_STATE(ksCurThread)->tcbEPPrev = NULL;
        NODE_STATE(ksCurThread)->tcbEPNext = NULL;

        /* Set head/tail of queue and endpoint state. */
        endpoint_ptr_set_epQueue_head_np(ep_ptr, TCB_REF(NODE_STATE(ksCurThread)));
        endpoint_ptr_mset_epQueue_tail_state(ep_ptr, TCB_REF(NODE_STATE(ksCurThread)),
                                             EPState_Recv);
    } else {
        /* Append current thread onto the queue. */
        endpointTail->tcbEPNext = NODE_STATE(ksCurThread);
        NODE_STATE(ksCurThread)->tcbEPPrev = endpointTail;
        NODE_STATE(ksCurThread)->tcbEPNext = NULL;

        /* Update tail of queue. */
        endpoint_ptr_mset_epQueue_tail_state(ep_ptr, TCB_REF(NODE_STATE(ksCurThread)),
                                             EPState_Recv);
    }

    /* Delete the reply cap. */
    mdb_node_ptr_mset_mdbNext_mdbRevocable_mdbFirstBadged(
        &CTE_PTR(mdb_node_get_mdbPrev(callerSlot->cteMDBNode))->cteMDBNode,
        0, 1, 1);
    callerSlot->cap = cap_null_cap_new();
    callerSlot->cteMDBNode = nullMDBNode;

    /* I know there's no fault, so straight to the transfer. */

    /* Replies don't have a badge. */
    badge = 0;

    fastpath_copy_mrs(length, NODE_STATE(ksCurThread), caller);

    /* Dest thread is set Running, but not queued. */
    thread_state_ptr_set_tsType_np(&caller->tcbState,
                                   ThreadState_Running);
    switchToThread_fp(caller, cap_pd, stored_hw_asid);

    msgInfo = wordFromMessageInfo(seL4_MessageInfo_set_capsUnwrapped(info, 0));

    fastpath_restore(badge, msgInfo, NODE_STATE(ksCurThread));
}
Exemple #8
0
void
#ifdef ARCH_X86
NORETURN
#endif
fastpath_call(word_t cptr, word_t msgInfo)
{
    seL4_MessageInfo_t info;
    cap_t ep_cap;
    endpoint_t *ep_ptr;
    word_t length;
    tcb_t *dest;
    word_t badge;
    cte_t *replySlot, *callerSlot;
    cap_t newVTable;
    vspace_root_t *cap_pd;
    pde_t stored_hw_asid;
    word_t fault_type;
    dom_t dom;
    word_t replyCanGrant;

    /* Get message info, length, and fault type. */
    info = messageInfoFromWord_raw(msgInfo);
    length = seL4_MessageInfo_get_length(info);
    fault_type = seL4_Fault_get_seL4_FaultType(NODE_STATE(ksCurThread)->tcbFault);

    /* Check there's no extra caps, the length is ok and there's no
     * saved fault. */
    if (unlikely(fastpath_mi_check(msgInfo) ||
                 fault_type != seL4_Fault_NullFault)) {
        slowpath(SysCall);
    }

    /* Lookup the cap */
    ep_cap = lookup_fp(TCB_PTR_CTE_PTR(NODE_STATE(ksCurThread), tcbCTable)->cap, cptr);

    /* Check it's an endpoint */
    if (unlikely(!cap_capType_equals(ep_cap, cap_endpoint_cap) ||
                 !cap_endpoint_cap_get_capCanSend(ep_cap))) {
        slowpath(SysCall);
    }

    /* Get the endpoint address */
    ep_ptr = EP_PTR(cap_endpoint_cap_get_capEPPtr(ep_cap));

    /* Get the destination thread, which is only going to be valid
     * if the endpoint is valid. */
    dest = TCB_PTR(endpoint_ptr_get_epQueue_head(ep_ptr));

    /* Check that there's a thread waiting to receive */
    if (unlikely(endpoint_ptr_get_state(ep_ptr) != EPState_Recv)) {
        slowpath(SysCall);
    }

    /* ensure we are not single stepping the destination in ia32 */
#if defined(CONFIG_HARDWARE_DEBUG_API) && defined(CONFIG_ARCH_IA32)
    if (dest->tcbArch.tcbContext.breakpointState.single_step_enabled) {
        slowpath(SysCall);
    }
#endif

    /* Get destination thread.*/
    newVTable = TCB_PTR_CTE_PTR(dest, tcbVTable)->cap;

    /* Get vspace root. */
    cap_pd = cap_vtable_cap_get_vspace_root_fp(newVTable);

    /* Ensure that the destination has a valid VTable. */
    if (unlikely(! isValidVTableRoot_fp(newVTable))) {
        slowpath(SysCall);
    }

#ifdef CONFIG_ARCH_AARCH32
    /* Get HW ASID */
    stored_hw_asid = cap_pd[PD_ASID_SLOT];
#endif

#ifdef CONFIG_ARCH_X86_64
    /* borrow the stored_hw_asid for PCID */
    stored_hw_asid.words[0] = cap_pml4_cap_get_capPML4MappedASID_fp(newVTable);
#endif

#ifdef CONFIG_ARCH_AARCH64
    stored_hw_asid.words[0] = cap_page_global_directory_cap_get_capPGDMappedASID(newVTable);
#endif

#ifdef CONFIG_ARCH_RISCV
    /* Get HW ASID */
    stored_hw_asid.words[0] = cap_page_table_cap_get_capPTMappedASID(newVTable);
#endif

    /* let gcc optimise this out for 1 domain */
    dom = maxDom ? ksCurDomain : 0;
    /* ensure only the idle thread or lower prio threads are present in the scheduler */
    if (likely(dest->tcbPriority < NODE_STATE(ksCurThread->tcbPriority)) &&
        !isHighestPrio(dom, dest->tcbPriority)) {
        slowpath(SysCall);
    }

    /* Ensure that the endpoint has has grant or grant-reply rights so that we can
     * create the reply cap */
    if (unlikely(!cap_endpoint_cap_get_capCanGrant(ep_cap) &&
                 !cap_endpoint_cap_get_capCanGrantReply(ep_cap))) {
        slowpath(SysCall);
    }

#ifdef CONFIG_ARCH_AARCH32
    if (unlikely(!pde_pde_invalid_get_stored_asid_valid(stored_hw_asid))) {
        slowpath(SysCall);
    }
#endif

    /* Ensure the original caller is in the current domain and can be scheduled directly. */
    if (unlikely(dest->tcbDomain != ksCurDomain && maxDom)) {
        slowpath(SysCall);
    }

#ifdef ENABLE_SMP_SUPPORT
    /* Ensure both threads have the same affinity */
    if (unlikely(NODE_STATE(ksCurThread)->tcbAffinity != dest->tcbAffinity)) {
        slowpath(SysCall);
    }
#endif /* ENABLE_SMP_SUPPORT */

    /*
     * --- POINT OF NO RETURN ---
     *
     * At this stage, we have committed to performing the IPC.
     */

#ifdef CONFIG_BENCHMARK_TRACK_KERNEL_ENTRIES
    ksKernelEntry.is_fastpath = true;
#endif

    /* Dequeue the destination. */
    endpoint_ptr_set_epQueue_head_np(ep_ptr, TCB_REF(dest->tcbEPNext));
    if (unlikely(dest->tcbEPNext)) {
        dest->tcbEPNext->tcbEPPrev = NULL;
    } else {
        endpoint_ptr_mset_epQueue_tail_state(ep_ptr, 0, EPState_Idle);
    }

    badge = cap_endpoint_cap_get_capEPBadge(ep_cap);

    /* Block sender */
    thread_state_ptr_set_tsType_np(&NODE_STATE(ksCurThread)->tcbState,
                                   ThreadState_BlockedOnReply);

    /* Get sender reply slot */
    replySlot = TCB_PTR_CTE_PTR(NODE_STATE(ksCurThread), tcbReply);

    /* Get dest caller slot */
    callerSlot = TCB_PTR_CTE_PTR(dest, tcbCaller);

    /* Insert reply cap */
    replyCanGrant = thread_state_ptr_get_blockingIPCCanGrant(&dest->tcbState);;
    cap_reply_cap_ptr_new_np(&callerSlot->cap, replyCanGrant, 0,
                             TCB_REF(NODE_STATE(ksCurThread)));
    mdb_node_ptr_set_mdbPrev_np(&callerSlot->cteMDBNode, CTE_REF(replySlot));
    mdb_node_ptr_mset_mdbNext_mdbRevocable_mdbFirstBadged(
        &replySlot->cteMDBNode, CTE_REF(callerSlot), 1, 1);

    fastpath_copy_mrs(length, NODE_STATE(ksCurThread), dest);

    /* Dest thread is set Running, but not queued. */
    thread_state_ptr_set_tsType_np(&dest->tcbState,
                                   ThreadState_Running);
    switchToThread_fp(dest, cap_pd, stored_hw_asid);

    msgInfo = wordFromMessageInfo(seL4_MessageInfo_set_capsUnwrapped(info, 0));

    fastpath_restore(badge, msgInfo, NODE_STATE(ksCurThread));
}
Exemple #9
0
exception_t
Arch_decodeIRQControlInvocation(word_t invLabel, word_t length, cte_t *srcSlot, extra_caps_t excaps, word_t *buffer)
{
    word_t index, depth;
    cte_t *destSlot;
    cap_t cnodeCap;
    lookupSlot_ret_t lu_ret;
    exception_t status;
    irq_t irq;
    word_t vector;

    if (!config_set(CONFIG_IRQ_IOAPIC)) {
        userError("IRQControl: Illegal operation.");
        current_syscall_error.type = seL4_IllegalOperation;
        return EXCEPTION_SYSCALL_ERROR;
    }

    /* check the common parameters */

    if (length < 7 || excaps.excaprefs[0] == NULL) {
        userError("IRQControl: Truncated message");
        current_syscall_error.type = seL4_TruncatedMessage;
        return EXCEPTION_SYSCALL_ERROR;
    }
    index = getSyscallArg(0, buffer);
    depth = getSyscallArg(1, buffer);
    cnodeCap = excaps.excaprefs[0]->cap;
    irq = getSyscallArg(6, buffer);
    if (irq > irq_user_max - irq_user_min) {
        userError("IRQControl: Invalid irq %ld should be between 0-%ld", (long)irq, (long)(irq_user_max - irq_user_min - 1));
        current_syscall_error.type = seL4_RangeError;
        current_syscall_error.rangeErrorMin = 0;
        current_syscall_error.rangeErrorMax = irq_user_max - irq_user_min;
        return EXCEPTION_SYSCALL_ERROR;
    }
    irq += irq_user_min;
    vector = (word_t)irq + IRQ_INT_OFFSET;

    lu_ret = lookupTargetSlot(cnodeCap, index, depth);
    if (lu_ret.status != EXCEPTION_NONE) {
        return lu_ret.status;
    }

    destSlot = lu_ret.slot;

    status = ensureEmptySlot(destSlot);
    if (status != EXCEPTION_NONE) {
        return status;
    }

    switch (invLabel) {
    case X86IRQIssueIRQHandlerIOAPIC: {
        word_t ioapic = getSyscallArg(2, buffer);
        word_t pin = getSyscallArg(3, buffer);
        word_t level = getSyscallArg(4, buffer);
        word_t polarity = getSyscallArg(5, buffer);


        if (isIRQActive(irq)) {
            userError("IOAPICGet: IRQ %d is already active.", (int)irq);
            current_syscall_error.type = seL4_RevokeFirst;
            return EXCEPTION_SYSCALL_ERROR;
        }

        status = ioapic_decode_map_pin_to_vector(ioapic, pin, level, polarity, vector);
        if (status != EXCEPTION_NONE) {
            return status;
        }

        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        return invokeIssueIRQHandlerIOAPIC(irq, ioapic, pin, level, polarity, vector, destSlot, srcSlot);
    }
    break;
    case X86IRQIssueIRQHandlerMSI: {
        word_t pci_bus = getSyscallArg(2, buffer);
        word_t pci_dev = getSyscallArg(3, buffer);
        word_t pci_func = getSyscallArg(4, buffer);
        word_t handle = getSyscallArg(5, buffer);
        x86_irq_state_t irqState;
        /* until we support msi interrupt remaping through vt-d we ignore the
         * vector and trust the user */
        (void)vector;
        if (isIRQActive(irq)) {
            current_syscall_error.type = seL4_RevokeFirst;
            return EXCEPTION_SYSCALL_ERROR;
        }

        if (pci_bus > PCI_BUS_MAX) {
            current_syscall_error.type = seL4_RangeError;
            current_syscall_error.rangeErrorMin = 0;
            current_syscall_error.rangeErrorMax = PCI_BUS_MAX;
            return EXCEPTION_SYSCALL_ERROR;
        }

        if (pci_dev > PCI_DEV_MAX) {
            current_syscall_error.type = seL4_RangeError;
            current_syscall_error.rangeErrorMin = 0;
            current_syscall_error.rangeErrorMax = PCI_DEV_MAX;
            return EXCEPTION_SYSCALL_ERROR;
        }

        if (pci_func > PCI_FUNC_MAX) {
            current_syscall_error.type = seL4_RangeError;
            current_syscall_error.rangeErrorMin = 0;
            current_syscall_error.rangeErrorMax = PCI_FUNC_MAX;
            return EXCEPTION_SYSCALL_ERROR;
        }

        irqState = x86_irq_state_irq_msi_new(pci_bus, pci_dev, pci_func, handle);

        setThreadState(NODE_STATE(ksCurThread), ThreadState_Restart);
        return Arch_invokeIRQControl(irq, destSlot, srcSlot, irqState);
    }
    break;
    default:
        userError("IRQControl: Illegal operation.");
        current_syscall_error.type = seL4_IllegalOperation;
        return EXCEPTION_SYSCALL_ERROR;
    }
}