msm8996-common: Import IPACM back

 * QC package: LA.UM.6.5.r1-05300-8x96.0

 * Squashed with commits 08e2a5b9b, 055b183 and 8fcf57b

Change-Id: I2f7a792dc0155986e065d1bf79e1f08370c3d79c
Signed-off-by: Davide Garberi <dade.garberi@gmail.com>

1 files changed, 612 insertions, 0 deletions

diff --git a/data-ipa-cfg-mgr/hal/src/HAL.cpp b/data-ipa-cfg-mgr/hal/src/HAL.cpp
new file mode 100644
index 0000000..002bbb4
--- /dev/null
+++ b/data-ipa-cfg-mgr/hal/src/HAL.cpp
@@ -0,0 +1,612 @@
+/*
+ * Copyright (c) 2017, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *    * Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *    * Redistributions in binary form must reproduce the above
+ *      copyright notice, this list of conditions and the following
+ *      disclaimer in the documentation and/or other materials provided
+ *      with the distribution.
+ *    * Neither the name of The Linux Foundation nor the names of its
+ *      contributors may be used to endorse or promote products derived
+ *      from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef DBG
+    #define DBG true
+#endif /* DBG */
+#define LOG_TAG "IPAHALService"
+
+/* HIDL Includes */
+#include <hwbinder/IPCThreadState.h>
+#include <hwbinder/ProcessState.h>
+
+/* Kernel Includes */
+#include <linux/netfilter/nfnetlink_compat.h>
+
+/* External Includes */
+#include <cutils/log.h>
+#include <cstring>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <vector>
+
+/* Internal Includes */
+#include "HAL.h"
+#include "LocalLogBuffer.h"
+#include "PrefixParser.h"
+
+/* Namespace pollution avoidance */
+using ::android::hardware::Void;
+using ::android::status_t;
+
+using RET = ::IOffloadManager::RET;
+using Prefix = ::IOffloadManager::Prefix;
+
+using ::std::map;
+using ::std::vector;
+
+
+/* ------------------------------ PUBLIC ------------------------------------ */
+HAL* HAL::makeIPAHAL(int version, IOffloadManager* mgr) {
+    if (DBG)
+        ALOGI("makeIPAHAL(%d, %s)", version,
+                (mgr != nullptr) ? "provided" : "null");
+    if (nullptr == mgr) return NULL;
+    else if (version != 1) return NULL;
+    HAL* ret = new HAL(mgr);
+    if (nullptr == ret) return NULL;
+    configureRpcThreadpool(1, false);
+    ret->registerAsSystemService("ipacm");
+    return ret;
+} /* makeIPAHAL */
+
+
+/* ------------------------------ PRIVATE ----------------------------------- */
+HAL::HAL(IOffloadManager* mgr) : mLogs("HAL Function Calls", 50) {
+    mIPA = mgr;
+    mCb.clear();
+    mCbIpa = nullptr;
+    mCbCt = nullptr;
+} /* HAL */
+
+void HAL::registerAsSystemService(const char* name) {
+    status_t ret = 0;
+
+    ret = IOffloadControl::registerAsService();
+    if (ret != 0) ALOGE("Failed to register IOffloadControl (%d)", ret);
+    else if (DBG) {
+        ALOGI("Successfully registered IOffloadControl");
+    }
+
+    ret = IOffloadConfig::registerAsService();
+    if (ret != 0) ALOGE("Failed to register IOffloadConfig (%d)", ret);
+    else if (DBG) {
+        ALOGI("Successfully registered IOffloadConfig");
+    }
+} /* registerAsSystemService */
+
+void HAL::doLogcatDump() {
+    ALOGD("mHandles");
+    ALOGD("========");
+    /* @TODO This will segfault if they aren't initialized and I don't currently
+     * care to check for initialization in a function that isn't used anyways
+     * ALOGD("fd1->%d", mHandle1->data[0]);
+     * ALOGD("fd2->%d", mHandle2->data[0]);
+     */
+    ALOGD("========");
+} /* doLogcatDump */
+
+HAL::BoolResult HAL::makeInputCheckFailure(string customErr) {
+    BoolResult ret;
+    ret.success = false;
+    ret.errMsg = "Failed Input Checks: " + customErr;
+    return ret;
+} /* makeInputCheckFailure */
+
+HAL::BoolResult HAL::ipaResultToBoolResult(RET in) {
+    BoolResult ret;
+    ret.success = (in >= RET::SUCCESS);
+    switch (in) {
+        case RET::FAIL_TOO_MANY_PREFIXES:
+            ret.errMsg = "Too Many Prefixes Provided";
+            break;
+        case RET::FAIL_UNSUPPORTED:
+            ret.errMsg = "Unsupported by Hardware";
+            break;
+        case RET::FAIL_INPUT_CHECK:
+            ret.errMsg = "Failed Input Checks";
+            break;
+        case RET::FAIL_HARDWARE:
+            ret.errMsg = "Hardware did not accept";
+            break;
+        case RET::FAIL_TRY_AGAIN:
+            ret.errMsg = "Try Again";
+            break;
+        case RET::SUCCESS:
+            ret.errMsg = "Successful";
+            break;
+        case RET::SUCCESS_DUPLICATE_CONFIG:
+            ret.errMsg = "Successful: Was a duplicate configuration";
+            break;
+        case RET::SUCCESS_NO_OP:
+            ret.errMsg = "Successful: No action needed";
+            break;
+        case RET::SUCCESS_OPTIMIZED:
+            ret.errMsg = "Successful: Performed optimized version of action";
+            break;
+        default:
+            ret.errMsg = "Unknown Error";
+            break;
+    }
+    return ret;
+} /* ipaResultToBoolResult */
+
+/* This will likely always result in doubling the number of loops the execution
+ * goes through.  Obviously that is suboptimal.  But if we first translate
+ * away from all HIDL specific code, then we can avoid sprinkling HIDL
+ * dependencies everywhere.
+ */
+vector<string> HAL::convertHidlStrToStdStr(hidl_vec<hidl_string> in) {
+    vector<string> ret;
+    for (size_t i = 0; i < in.size(); i++) {
+        string add = in[i];
+        ret.push_back(add);
+    }
+    return ret;
+} /* convertHidlStrToStdStr */
+
+void HAL::registerEventListeners() {
+    registerIpaCb();
+    registerCtCb();
+} /* registerEventListeners */
+
+void HAL::registerIpaCb() {
+    if (isInitialized() && mCbIpa == nullptr) {
+        LocalLogBuffer::FunctionLog fl("registerEventListener");
+        mCbIpa = new IpaEventRelay(mCb);
+        mIPA->registerEventListener(mCbIpa);
+        mLogs.addLog(fl);
+    } else {
+        ALOGE("Failed to registerIpaCb (isInitialized()=%s, (mCbIpa == nullptr)=%s)",
+                isInitialized() ? "true" : "false",
+                (mCbIpa == nullptr) ? "true" : "false");
+    }
+} /* registerIpaCb */
+
+void HAL::registerCtCb() {
+    if (isInitialized() && mCbCt == nullptr) {
+        LocalLogBuffer::FunctionLog fl("registerCtTimeoutUpdater");
+        mCbCt = new CtUpdateAmbassador(mCb);
+        mIPA->registerCtTimeoutUpdater(mCbCt);
+        mLogs.addLog(fl);
+    } else {
+        ALOGE("Failed to registerCtCb (isInitialized()=%s, (mCbCt == nullptr)=%s)",
+                isInitialized() ? "true" : "false",
+                (mCbCt == nullptr) ? "true" : "false");
+    }
+} /* registerCtCb */
+
+void HAL::unregisterEventListeners() {
+    unregisterIpaCb();
+    unregisterCtCb();
+} /* unregisterEventListeners */
+
+void HAL::unregisterIpaCb() {
+    if (mCbIpa != nullptr) {
+        LocalLogBuffer::FunctionLog fl("unregisterEventListener");
+        mIPA->unregisterEventListener(mCbIpa);
+        mCbIpa = nullptr;
+        mLogs.addLog(fl);
+    } else {
+        ALOGE("Failed to unregisterIpaCb");
+    }
+} /* unregisterIpaCb */
+
+void HAL::unregisterCtCb() {
+    if (mCbCt != nullptr) {
+        LocalLogBuffer::FunctionLog fl("unregisterCtTimeoutUpdater");
+        mIPA->unregisterCtTimeoutUpdater(mCbCt);
+        mCbCt = nullptr;
+        mLogs.addLog(fl);
+    } else {
+        ALOGE("Failed to unregisterCtCb");
+    }
+} /* unregisterCtCb */
+
+void HAL::clearHandles() {
+    ALOGI("clearHandles()");
+    /* @TODO handle this more gracefully... also remove the log
+     *
+     * Things that would be nice, but I can't do:
+     * [1] Destroy the object (it's on the stack)
+     * [2] Call freeHandle (it's private)
+     *
+     * Things I can do but are hacks:
+     * [1] Look at code and notice that setTo immediately calls freeHandle
+     */
+    mHandle1.setTo(nullptr, true);
+    mHandle2.setTo(nullptr, true);
+} /* clearHandles */
+
+bool HAL::isInitialized() {
+    return mCb.get() != nullptr;
+} /* isInitialized */
+
+
+/* -------------------------- IOffloadConfig -------------------------------- */
+Return<void> HAL::setHandles(
+    const hidl_handle &fd1,
+    const hidl_handle &fd2,
+    setHandles_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+
+    if (fd1->numFds != 1) {
+        BoolResult res = makeInputCheckFailure("Must provide exactly one FD per handle (fd1)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+
+        mLogs.addLog(fl);
+        return Void();
+    }
+
+    if (fd2->numFds != 1) {
+        BoolResult res = makeInputCheckFailure("Must provide exactly one FD per handle (fd2)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+
+        mLogs.addLog(fl);
+        return Void();
+    }
+
+    /* The = operator calls freeHandle internally.  Therefore, if we were using
+     * these handles previously, they're now gone... forever.  But hopefully the
+     * new ones kick in very quickly.
+     *
+     * After freeing anything previously held, it will dup the FD so we have our
+     * own copy.
+     */
+    mHandle1 = fd1;
+    mHandle2 = fd2;
+
+    /* Log the DUPed FD instead of the actual input FD so that we can lookup
+     * this value in ls -l /proc/<pid>/<fd>
+     */
+    fl.addArg("fd1", mHandle1->data[0]);
+    fl.addArg("fd2", mHandle2->data[0]);
+
+    /* Try to provide each handle to IPACM.  Destroy our DUPed hidl_handles if
+     * IPACM does not like either input.  This keeps us from leaking FDs or
+     * providing half solutions.
+     *
+     * @TODO unfortunately, this does not cover duplicate configs where IPACM
+     * thinks it is still holding on to a handle that we would have freed above.
+     * It also probably means that IPACM would not know about the first FD being
+     * freed if it rejects the second FD.
+     */
+    RET ipaReturn = mIPA->provideFd(mHandle1->data[0], UDP_SUBSCRIPTIONS);
+    if (ipaReturn == RET::SUCCESS) {
+        ipaReturn = mIPA->provideFd(mHandle2->data[0], TCP_SUBSCRIPTIONS);
+    }
+
+    if (ipaReturn != RET::SUCCESS) {
+        ALOGE("IPACM failed to accept the FDs (%d %d)", mHandle1->data[0],
+                mHandle2->data[0]);
+        clearHandles();
+    } else {
+        /* @TODO remove logs after stabilization */
+        ALOGI("IPACM was provided two FDs (%d, %d)", mHandle1->data[0],
+                mHandle2->data[0]);
+    }
+
+    BoolResult res = ipaResultToBoolResult(ipaReturn);
+    hidl_cb(res.success, res.errMsg);
+
+    fl.setResult(res.success, res.errMsg);
+    mLogs.addLog(fl);
+    return Void();
+} /* setHandles */
+
+
+/* -------------------------- IOffloadControl ------------------------------- */
+Return<void> HAL::initOffload
+(
+    const ::android::sp<ITetheringOffloadCallback>& cb,
+    initOffload_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+
+    if (isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Already initialized");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+        mLogs.addLog(fl);
+    } else {
+        /* Should storing the CB be a function? */
+        mCb = cb;
+        registerEventListeners();
+        BoolResult res = ipaResultToBoolResult(RET::SUCCESS);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+        mLogs.addLog(fl);
+    }
+
+    return Void();
+} /* initOffload */
+
+Return<void> HAL::stopOffload
+(
+    stopOffload_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Was never initialized");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+        mLogs.addLog(fl);
+    } else {
+        /* Should removing the CB be a function? */
+        mCb.clear();
+        unregisterEventListeners();
+
+        RET ipaReturn = mIPA->stopAllOffload();
+        if (ipaReturn != RET::SUCCESS) {
+            /* Ignore IPAs return value here and provide why stopAllOffload
+             * failed.  However, if IPA failed to clearAllFds, then we can't
+             * clear our map because they may still be in use.
+             */
+            RET ret = mIPA->clearAllFds();
+            if (ret == RET::SUCCESS) {
+                clearHandles();
+            }
+        } else {
+            ipaReturn = mIPA->clearAllFds();
+            /* If IPA fails, they may still be using these for some reason. */
+            if (ipaReturn == RET::SUCCESS) {
+                clearHandles();
+            } else {
+                ALOGE("IPACM failed to return success for clearAllFds so they will not be released...");
+            }
+        }
+
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+
+        fl.setResult(res.success, res.errMsg);
+        mLogs.addLog(fl);
+    }
+
+    return Void();
+} /* stopOffload */
+
+Return<void> HAL::setLocalPrefixes
+(
+    const hidl_vec<hidl_string>& prefixes,
+    setLocalPrefixes_cb hidl_cb
+) {
+    BoolResult res;
+    PrefixParser parser;
+    vector<string> prefixesStr = convertHidlStrToStdStr(prefixes);
+
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("prefixes", prefixesStr);
+
+    memset(&res,0,sizeof(BoolResult));
+
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Not initialized");
+    } else if(prefixesStr.size() < 1) {
+        res = ipaResultToBoolResult(RET::FAIL_INPUT_CHECK);
+    } else if (!parser.add(prefixesStr)) {
+        res = makeInputCheckFailure(parser.getLastErrAsStr());
+    } else {
+        res = ipaResultToBoolResult(RET::SUCCESS);
+    }
+
+    hidl_cb(res.success, res.errMsg);
+    fl.setResult(res.success, res.errMsg);
+    mLogs.addLog(fl);
+    return Void();
+} /* setLocalPrefixes */
+
+Return<void> HAL::getForwardedStats
+(
+    const hidl_string& upstream,
+    getForwardedStats_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("upstream", upstream);
+
+    OffloadStatistics ret;
+    RET ipaReturn = mIPA->getStats(upstream.c_str(), true, ret);
+    if (ipaReturn == RET::SUCCESS) {
+        hidl_cb(ret.getTotalRxBytes(), ret.getTotalTxBytes());
+        fl.setResult(ret.getTotalRxBytes(), ret.getTotalTxBytes());
+    } else {
+        /* @TODO Ensure the output is zeroed, but this is probably not enough to
+         * tell Framework that an error has occurred.  If, for example, they had
+         * not yet polled for statistics previously, they may incorrectly assume
+         * that simply no statistics have transpired on hardware path.
+         *
+         * Maybe ITetheringOffloadCallback:onEvent(OFFLOAD_STOPPED_ERROR) is
+         * enough to handle this case, time will tell.
+         */
+        hidl_cb(0, 0);
+        fl.setResult(0, 0);
+    }
+
+    mLogs.addLog(fl);
+    return Void();
+} /* getForwardedStats */
+
+Return<void> HAL::setDataLimit
+(
+    const hidl_string& upstream,
+    uint64_t limit,
+    setDataLimit_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("upstream", upstream);
+    fl.addArg("limit", limit);
+
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Not initialized (setDataLimit)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else {
+        RET ipaReturn = mIPA->setQuota(upstream.c_str(), limit);
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+
+    mLogs.addLog(fl);
+    return Void();
+} /* setDataLimit */
+
+Return<void> HAL::setUpstreamParameters
+(
+    const hidl_string& iface,
+    const hidl_string& v4Addr,
+    const hidl_string& v4Gw,
+    const hidl_vec<hidl_string>& v6Gws,
+    setUpstreamParameters_cb hidl_cb
+) {
+    vector<string> v6GwStrs = convertHidlStrToStdStr(v6Gws);
+
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("iface", iface);
+    fl.addArg("v4Addr", v4Addr);
+    fl.addArg("v4Gw", v4Gw);
+    fl.addArg("v6Gws", v6GwStrs);
+
+    PrefixParser v4AddrParser;
+    PrefixParser v4GwParser;
+    PrefixParser v6GwParser;
+
+    /* @TODO maybe we should enforce that these addresses and gateways are fully
+     * qualified here.  But then, how do we allow them to be empty/null as well
+     * while still preserving a sane API on PrefixParser?
+     */
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Not initialized (setUpstreamParameters)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else if (!v4AddrParser.addV4(v4Addr) && !v4Addr.empty()) {
+        BoolResult res = makeInputCheckFailure(v4AddrParser.getLastErrAsStr());
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else if (!v4GwParser.addV4(v4Gw) && !v4Gw.empty()) {
+        BoolResult res = makeInputCheckFailure(v4GwParser.getLastErrAsStr());
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else if (v6GwStrs.size() >= 1 && !v6GwParser.addV6(v6GwStrs)) {
+        BoolResult res = makeInputCheckFailure(v6GwParser.getLastErrAsStr());
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else if (iface.size()>= 1) {
+        RET ipaReturn = mIPA->setUpstream(
+                iface.c_str(),
+                v4GwParser.getFirstPrefix(),
+                v6GwParser.getFirstPrefix());
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else {
+	/* send NULL iface string when upstream down */
+        RET ipaReturn = mIPA->setUpstream(
+                NULL,
+                v4GwParser.getFirstPrefix(IP_FAM::V4),
+                v6GwParser.getFirstPrefix(IP_FAM::V6));
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+
+    mLogs.addLog(fl);
+    return Void();
+} /* setUpstreamParameters */
+
+Return<void> HAL::addDownstream
+(
+    const hidl_string& iface,
+    const hidl_string& prefix,
+    addDownstream_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("iface", iface);
+    fl.addArg("prefix", prefix);
+
+    PrefixParser prefixParser;
+
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Not initialized (setUpstreamParameters)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+    else if (!prefixParser.add(prefix)) {
+        BoolResult res = makeInputCheckFailure(prefixParser.getLastErrAsStr());
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else {
+        RET ipaReturn = mIPA->addDownstream(
+                iface.c_str(),
+                prefixParser.getFirstPrefix());
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+
+    mLogs.addLog(fl);
+    return Void();
+} /* addDownstream */
+
+Return<void> HAL::removeDownstream
+(
+    const hidl_string& iface,
+    const hidl_string& prefix,
+    removeDownstream_cb hidl_cb
+) {
+    LocalLogBuffer::FunctionLog fl(__func__);
+    fl.addArg("iface", iface);
+    fl.addArg("prefix", prefix);
+
+    PrefixParser prefixParser;
+
+    if (!isInitialized()) {
+        BoolResult res = makeInputCheckFailure("Not initialized (setUpstreamParameters)");
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+    else if (!prefixParser.add(prefix)) {
+        BoolResult res = makeInputCheckFailure(prefixParser.getLastErrAsStr());
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    } else {
+        RET ipaReturn = mIPA->removeDownstream(
+                iface.c_str(),
+                prefixParser.getFirstPrefix());
+        BoolResult res = ipaResultToBoolResult(ipaReturn);
+        hidl_cb(res.success, res.errMsg);
+        fl.setResult(res.success, res.errMsg);
+    }
+
+    mLogs.addLog(fl);
+    return Void();
+} /* removeDownstream */