IdleMaint.cpp - SHIFTPHONES/android_system_vold - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "IdleMaint.h"
 #include "FileDeviceUtils.h"
 #include "Utils.h"
 #include "VoldUtil.h"
 #include "VolumeManager.h"
 #include "model/PrivateVolume.h"

 #include <thread>
 #include <utility>

 #include <aidl/android/hardware/health/storage/BnGarbageCollectCallback.h>
 #include <aidl/android/hardware/health/storage/IStorage.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <android/binder_manager.h>
 #include <android/hardware/health/storage/1.0/IStorage.h>
 #include <fs_mgr.h>
 #include <private/android_filesystem_config.h>
 #include <wakelock/wakelock.h>

 #include <dirent.h>
 #include <fcntl.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>

 using android::base::Basename;
 using android::base::ReadFileToString;
 using android::base::Realpath;
 using android::base::StringPrintf;
 using android::base::Timer;
 using android::base::WriteStringToFile;
 using android::hardware::Return;
 using android::hardware::Void;
 using AStorage = aidl::android::hardware::health::storage::IStorage;
 using ABnGarbageCollectCallback =
         aidl::android::hardware::health::storage::BnGarbageCollectCallback;
 using AResult = aidl::android::hardware::health::storage::Result;
 using HStorage = android::hardware::health::storage::V1_0::IStorage;
 using HGarbageCollectCallback = android::hardware::health::storage::V1_0::IGarbageCollectCallback;
 using HResult = android::hardware::health::storage::V1_0::Result;
 using std::string_literals::operator""s;

 namespace android {
 namespace vold {

 enum class PathTypes {
     kMountPoint = 1,
     kBlkDevice,
 };

 enum class IdleMaintStats {
     kStopped = 1,
     kRunning,
     kAbort,
 };

 static const char* kWakeLock = "IdleMaint";
 static const int DIRTY_SEGMENTS_THRESHOLD = 100;
 /*
  * Timing policy:
  *  1. F2FS_GC = 7 mins
  *  2. Trim = 1 min
  *  3. Dev GC = 2 mins
  */
 static const int GC_TIMEOUT_SEC = 420;
 static const int DEVGC_TIMEOUT_SEC = 120;
 static const int KBYTES_IN_SEGMENT = 2048;
 static const int MIN_GC_URGENT_SLEEP_TIME = 500;
 static const int ONE_MINUTE_IN_MS = 60000;
 static const int GC_NORMAL_MODE = 0;
 static const int GC_URGENT_MID_MODE = 3;

 static int32_t previousSegmentWrite = 0;

 static IdleMaintStats idle_maint_stat(IdleMaintStats::kStopped);
 static std::condition_variable cv_abort, cv_stop;
 static std::mutex cv_m;

 static void addFromVolumeManager(std::list<std::string>* paths, PathTypes path_type) {
     VolumeManager* vm = VolumeManager::Instance();
     std::list<std::string> privateIds;
     vm->listVolumes(VolumeBase::Type::kPrivate, privateIds);
     for (const auto& id : privateIds) {
         PrivateVolume* vol = static_cast<PrivateVolume*>(vm->findVolume(id).get());
         if (vol != nullptr && vol->getState() == VolumeBase::State::kMounted) {
             if (path_type == PathTypes::kMountPoint) {
                 paths->push_back(vol->getPath());
             } else if (path_type == PathTypes::kBlkDevice) {
                 std::string gc_path;
                 const std::string& fs_type = vol->getFsType();
                 if (fs_type == "f2fs" && (Realpath(vol->getRawDmDevPath(), &gc_path) ||
                                           Realpath(vol->getRawDevPath(), &gc_path))) {
                     paths->push_back(std::string("/sys/fs/") + fs_type + "/" + Basename(gc_path));
                 }
             }
         }
     }
 }

 static void addFromFstab(std::list<std::string>* paths, PathTypes path_type, bool only_data_part) {
     std::string previous_mount_point;
     for (const auto& entry : fstab_default) {
         // Skip raw partitions and swap space.
         if (entry.fs_type == "emmc" || entry.fs_type == "mtd" || entry.fs_type == "swap") {
             continue;
         }
         // Skip read-only filesystems and bind mounts.
         if (entry.flags & (MS_RDONLY | MS_BIND)) {
             continue;
         }
         // Skip anything without an underlying block device, e.g. virtiofs.
         if (entry.blk_device[0] != '/') {
             continue;
         }
         if (entry.fs_mgr_flags.vold_managed) {
             continue;  // Should we trim fat32 filesystems?
         }
         if (entry.fs_mgr_flags.no_trim) {
             continue;
         }

         if (only_data_part && entry.mount_point != "/data") {
             continue;
         }

         // Skip the multi-type partitions, which are required to be following each other.
         // See fs_mgr.c's mount_with_alternatives().
         if (entry.mount_point == previous_mount_point) {
             continue;
         }

         if (path_type == PathTypes::kMountPoint) {
             paths->push_back(entry.mount_point);
         } else if (path_type == PathTypes::kBlkDevice) {
             std::string path;
             if (entry.fs_type == "f2fs" &&
                 Realpath(android::vold::BlockDeviceForPath(entry.mount_point + "/"), &path)) {
                 paths->push_back("/sys/fs/" + entry.fs_type + "/" + Basename(path));
             }
         }

         previous_mount_point = entry.mount_point;
     }
 }

 void Trim(const android::sp<android::os::IVoldTaskListener>& listener) {
     auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
     if (!wl.has_value()) {
         return;
     }

     // Collect both fstab and vold volumes
     std::list<std::string> paths;
     addFromFstab(&paths, PathTypes::kMountPoint, false);
     addFromVolumeManager(&paths, PathTypes::kMountPoint);

     for (const auto& path : paths) {
         LOG(DEBUG) << "Starting trim of " << path;

         android::os::PersistableBundle extras;
         extras.putString(String16("path"), String16(path.c_str()));

         int fd = open(path.c_str(), O_RDONLY | O_DIRECTORY | O_CLOEXEC | O_NOFOLLOW);
         if (fd < 0) {
             PLOG(WARNING) << "Failed to open " << path;
             if (listener) {
                 listener->onStatus(-1, extras);
             }
             continue;
         }

         struct fstrim_range range;
         memset(&range, 0, sizeof(range));
         range.len = ULLONG_MAX;

         nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME);
         if (ioctl(fd, FITRIM, &range)) {
             PLOG(WARNING) << "Trim failed on " << path;
             if (listener) {
                 listener->onStatus(-1, extras);
             }
         } else {
             nsecs_t time = systemTime(SYSTEM_TIME_BOOTTIME) - start;
             LOG(INFO) << "Trimmed " << range.len << " bytes on " << path << " in "
                       << nanoseconds_to_milliseconds(time) << "ms";
             extras.putLong(String16("bytes"), range.len);
             extras.putLong(String16("time"), time);
             if (listener) {
                 listener->onStatus(0, extras);
             }
         }
         close(fd);
     }

     if (listener) {
         android::os::PersistableBundle extras;
         listener->onFinished(0, extras);
     }

 }

 static bool waitForGc(const std::list<std::string>& paths) {
     std::unique_lock<std::mutex> lk(cv_m, std::defer_lock);
     bool stop = false, aborted = false;
     Timer timer;

     while (!stop && !aborted) {
         stop = true;
         for (const auto& path : paths) {
             std::string dirty_segments;
             if (!ReadFileToString(path + "/dirty_segments", &dirty_segments)) {
                 PLOG(WARNING) << "Reading dirty_segments failed in " << path;
                 continue;
             }
             if (std::stoi(dirty_segments) > DIRTY_SEGMENTS_THRESHOLD) {
                 stop = false;
                 break;
             }
         }

         if (stop) break;

         if (timer.duration() >= std::chrono::seconds(GC_TIMEOUT_SEC)) {
             LOG(WARNING) << "GC timeout";
             break;
         }

         lk.lock();
         aborted =
             cv_abort.wait_for(lk, 10s, [] { return idle_maint_stat == IdleMaintStats::kAbort; });
         lk.unlock();
     }

     return aborted;
 }

 static int startGc(const std::list<std::string>& paths) {
     for (const auto& path : paths) {
         LOG(DEBUG) << "Start GC on " << path;
         if (!WriteStringToFile("1", path + "/gc_urgent")) {
             PLOG(WARNING) << "Start GC failed on " << path;
         }
     }
     return android::OK;
 }

 static int stopGc(const std::list<std::string>& paths) {
     for (const auto& path : paths) {
         LOG(DEBUG) << "Stop GC on " << path;
         if (!WriteStringToFile("0", path + "/gc_urgent")) {
             PLOG(WARNING) << "Stop GC failed on " << path;
         }
     }
     return android::OK;
 }

 static std::string getDevSysfsPath() {
     for (const auto& entry : fstab_default) {
         if (!entry.sysfs_path.empty()) {
             return entry.sysfs_path;
         }
     }
     LOG(WARNING) << "Cannot find dev sysfs path";
     return "";
 }

 static void runDevGcFstab(void) {
     std::string path = getDevSysfsPath();
     if (path.empty()) {
         return;
     }

     path = path + "/manual_gc";
     Timer timer;

     LOG(DEBUG) << "Start Dev GC on " << path;
     while (1) {
         std::string require;
         if (!ReadFileToString(path, &require)) {
             PLOG(WARNING) << "Reading manual_gc failed in " << path;
             break;
         }
         require = android::base::Trim(require);
         if (require == "" || require == "off" || require == "disabled") {
             LOG(DEBUG) << "No more to do Dev GC";
             break;
         }

         LOG(DEBUG) << "Trigger Dev GC on " << path;
         if (!WriteStringToFile("1", path)) {
             PLOG(WARNING) << "Start Dev GC failed on " << path;
             break;
         }

         if (timer.duration() >= std::chrono::seconds(DEVGC_TIMEOUT_SEC)) {
             LOG(WARNING) << "Dev GC timeout";
             break;
         }
         sleep(2);
     }
     LOG(DEBUG) << "Stop Dev GC on " << path;
     if (!WriteStringToFile("0", path)) {
         PLOG(WARNING) << "Stop Dev GC failed on " << path;
     }
     return;
 }

 enum class IDL { HIDL, AIDL };
 std::ostream& operator<<(std::ostream& os, IDL idl) {
     return os << (idl == IDL::HIDL ? "HIDL" : "AIDL");
 }

 template <IDL idl, typename Result>
 class GcCallbackImpl {
   protected:
     void onFinishInternal(Result result) {
         std::unique_lock<std::mutex> lock(mMutex);
         mFinished = true;
         mResult = result;
         lock.unlock();
         mCv.notify_all();
     }

   public:
     void wait(uint64_t seconds) {
         std::unique_lock<std::mutex> lock(mMutex);
         mCv.wait_for(lock, std::chrono::seconds(seconds), [this] { return mFinished; });

         if (!mFinished) {
             LOG(WARNING) << "Dev GC on " << idl << " HAL timeout";
         } else if (mResult != Result::SUCCESS) {
             LOG(WARNING) << "Dev GC on " << idl << " HAL failed with " << toString(mResult);
         } else {
             LOG(INFO) << "Dev GC on " << idl << " HAL successful";
         }
     }

   private:
     std::mutex mMutex;
     std::condition_variable mCv;
     bool mFinished{false};
     Result mResult{Result::UNKNOWN_ERROR};
 };

 class AGcCallbackImpl : public ABnGarbageCollectCallback,
                         public GcCallbackImpl<IDL::AIDL, AResult> {
     ndk::ScopedAStatus onFinish(AResult result) override {
         onFinishInternal(result);
         return ndk::ScopedAStatus::ok();
     }
 };

 class HGcCallbackImpl : public HGarbageCollectCallback, public GcCallbackImpl<IDL::HIDL, HResult> {
     Return<void> onFinish(HResult result) override {
         onFinishInternal(result);
         return Void();
     }
 };

 template <IDL idl, typename Service, typename GcCallbackImpl, typename GetDescription>
 static void runDevGcOnHal(Service service, GcCallbackImpl cb, GetDescription get_description) {
     LOG(DEBUG) << "Start Dev GC on " << idl << " HAL";
     auto ret = service->garbageCollect(DEVGC_TIMEOUT_SEC, cb);
     if (!ret.isOk()) {
         LOG(WARNING) << "Cannot start Dev GC on " << idl
                      << " HAL: " << std::invoke(get_description, ret);
         return;
     }
     cb->wait(DEVGC_TIMEOUT_SEC);
 }

 static void runDevGc(void) {
     auto aidl_service_name = AStorage::descriptor + "/default"s;
     if (AServiceManager_isDeclared(aidl_service_name.c_str())) {
         ndk::SpAIBinder binder(AServiceManager_waitForService(aidl_service_name.c_str()));
         if (binder.get() != nullptr) {
             std::shared_ptr<AStorage> aidl_service = AStorage::fromBinder(binder);
             if (aidl_service != nullptr) {
                 runDevGcOnHal<IDL::AIDL>(aidl_service, ndk::SharedRefBase::make<AGcCallbackImpl>(),
                                          &ndk::ScopedAStatus::getDescription);
                 return;
             }
         }
         LOG(WARNING) << "Device declares " << aidl_service_name
                      << " but it is not running, skip dev GC on AIDL HAL";
         return;
     }
     auto hidl_service = HStorage::getService();
     if (hidl_service != nullptr) {
         runDevGcOnHal<IDL::HIDL>(hidl_service, sp<HGcCallbackImpl>(new HGcCallbackImpl()),
                                  &Return<void>::description);
         return;
     }
     // fallback to legacy code path
     runDevGcFstab();
 }

 int RunIdleMaint(bool needGC, const android::sp<android::os::IVoldTaskListener>& listener) {
     std::unique_lock<std::mutex> lk(cv_m);
     bool gc_aborted = false;

     if (idle_maint_stat != IdleMaintStats::kStopped) {
         LOG(DEBUG) << "idle maintenance is already running";
         if (listener) {
             android::os::PersistableBundle extras;
             listener->onFinished(0, extras);
         }
         return android::OK;
     }
     idle_maint_stat = IdleMaintStats::kRunning;
     lk.unlock();

     LOG(DEBUG) << "idle maintenance started";

     auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
     if (!wl.has_value()) {
         return android::UNEXPECTED_NULL;
     }

     if (needGC) {
         std::list<std::string> paths;
         addFromFstab(&paths, PathTypes::kBlkDevice, false);
         addFromVolumeManager(&paths, PathTypes::kBlkDevice);

         startGc(paths);

         gc_aborted = waitForGc(paths);

         stopGc(paths);
     }

     lk.lock();
     idle_maint_stat = IdleMaintStats::kStopped;
     lk.unlock();

     cv_stop.notify_one();

     if (!gc_aborted) {
         Trim(nullptr);
         runDevGc();
     }

     if (listener) {
         android::os::PersistableBundle extras;
         listener->onFinished(0, extras);
     }

     LOG(DEBUG) << "idle maintenance completed";

     return android::OK;
 }

 int AbortIdleMaint(const android::sp<android::os::IVoldTaskListener>& listener) {
     auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
     if (!wl.has_value()) {
         return android::UNEXPECTED_NULL;
     }

     std::unique_lock<std::mutex> lk(cv_m);
     if (idle_maint_stat != IdleMaintStats::kStopped) {
         idle_maint_stat = IdleMaintStats::kAbort;
         lk.unlock();
         cv_abort.notify_one();
         lk.lock();
         LOG(DEBUG) << "aborting idle maintenance";
         cv_stop.wait(lk, [] { return idle_maint_stat == IdleMaintStats::kStopped; });
     }
     lk.unlock();

     if (listener) {
         android::os::PersistableBundle extras;
         listener->onFinished(0, extras);
     }

     LOG(DEBUG) << "idle maintenance stopped";

     return android::OK;
 }

 int getLifeTime(const std::string& path) {
     std::string result;

     if (!ReadFileToString(path, &result)) {
         PLOG(WARNING) << "Reading lifetime estimation failed for " << path;
         return -1;
     }
     return std::stoi(result, 0, 16);
 }

 int32_t GetStorageLifeTime() {
     std::string path = getDevSysfsPath();
     if (path.empty()) {
         return -1;
     }

     std::string lifeTimeBasePath = path + "/health_descriptor/life_time_estimation_";

     int32_t lifeTime = getLifeTime(lifeTimeBasePath + "c");
     if (lifeTime != -1) {
         return lifeTime;
     }

     int32_t lifeTimeA = getLifeTime(lifeTimeBasePath + "a");
     int32_t lifeTimeB = getLifeTime(lifeTimeBasePath + "b");
     lifeTime = std::max(lifeTimeA, lifeTimeB);
     if (lifeTime != -1) {
         return lifeTime == 0 ? -1 : lifeTime * 10;
     }
     return -1;
 }

 void SetGCUrgentPace(int32_t neededSegments, int32_t minSegmentThreshold, float dirtyReclaimRate,
                      float reclaimWeight, int32_t gcPeriod) {
     std::list<std::string> paths;
     bool needGC = true;

     addFromFstab(&paths, PathTypes::kBlkDevice, true);
     if (paths.empty()) {
         LOG(WARNING) << "There is no valid blk device path for data partition";
         return;
     }

     std::string f2fsSysfsPath = paths.front();
     std::string freeSegmentsPath = f2fsSysfsPath + "/free_segments";
     std::string dirtySegmentsPath = f2fsSysfsPath + "/dirty_segments";
     std::string gcSleepTimePath = f2fsSysfsPath + "/gc_urgent_sleep_time";
     std::string gcUrgentModePath = f2fsSysfsPath + "/gc_urgent";
     std::string freeSegmentsStr, dirtySegmentsStr;

     if (!ReadFileToString(freeSegmentsPath, &freeSegmentsStr)) {
         PLOG(WARNING) << "Reading failed in " << freeSegmentsPath;
         return;
     }

     if (!ReadFileToString(dirtySegmentsPath, &dirtySegmentsStr)) {
         PLOG(WARNING) << "Reading failed in " << dirtySegmentsPath;
         return;
     }

     int32_t freeSegments = std::stoi(freeSegmentsStr);
     int32_t dirtySegments = std::stoi(dirtySegmentsStr);

     neededSegments *= reclaimWeight;
     if (freeSegments >= neededSegments) {
         LOG(INFO) << "Enough free segments: " << freeSegments
                    << ", needed segments: " << neededSegments;
         needGC = false;
     } else if (freeSegments + dirtySegments < minSegmentThreshold) {
         LOG(INFO) << "The sum of free segments: " << freeSegments
                    << ", dirty segments: " << dirtySegments << " is under " << minSegmentThreshold;
         needGC = false;
     }

     if (!needGC) {
         if (!WriteStringToFile(std::to_string(GC_NORMAL_MODE), gcUrgentModePath)) {
             PLOG(WARNING) << "Writing failed in " << gcUrgentModePath;
         }
         return;
     }

     int32_t sleepTime;

     neededSegments -= freeSegments;
     neededSegments = std::min(neededSegments, (int32_t)(dirtySegments * dirtyReclaimRate));
     if (neededSegments == 0) {
         sleepTime = MIN_GC_URGENT_SLEEP_TIME;
     } else {
         sleepTime = gcPeriod * ONE_MINUTE_IN_MS / neededSegments;
         if (sleepTime < MIN_GC_URGENT_SLEEP_TIME) {
             sleepTime = MIN_GC_URGENT_SLEEP_TIME;
         }
     }
     if (!WriteStringToFile(std::to_string(sleepTime), gcSleepTimePath)) {
         PLOG(WARNING) << "Writing failed in " << gcSleepTimePath;
         return;
     }

     if (!WriteStringToFile(std::to_string(GC_URGENT_MID_MODE), gcUrgentModePath)) {
         PLOG(WARNING) << "Writing failed in " << gcUrgentModePath;
         return;
     }

     LOG(INFO) << "Successfully set gc urgent mode: "
                << "free segments: " << freeSegments << ", reclaim target: " << neededSegments
                << ", sleep time: " << sleepTime;
 }

 static int32_t getLifeTimeWrite() {
     std::list<std::string> paths;
     addFromFstab(&paths, PathTypes::kBlkDevice, true);
     if (paths.empty()) {
         LOG(WARNING) << "There is no valid blk device path for data partition";
         return -1;
     }

     std::string writeKbytesPath = paths.front() + "/lifetime_write_kbytes";
     std::string writeKbytesStr;
     if (!ReadFileToString(writeKbytesPath, &writeKbytesStr)) {
         PLOG(WARNING) << "Reading failed in " << writeKbytesPath;
         return -1;
     }

     long long writeBytes = std::stoll(writeKbytesStr);
     return writeBytes / KBYTES_IN_SEGMENT;
 }

 void RefreshLatestWrite() {
     int32_t segmentWrite = getLifeTimeWrite();
     if (segmentWrite != -1) {
         previousSegmentWrite = segmentWrite;
     }
 }

 int32_t GetWriteAmount() {
     int32_t currentSegmentWrite = getLifeTimeWrite();
     if (currentSegmentWrite == -1) {
         return -1;
     }

     int32_t writeAmount = currentSegmentWrite - previousSegmentWrite;
     previousSegmentWrite = currentSegmentWrite;
     return writeAmount;
 }

 }  // namespace vold
 }  // namespace android
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "IdleMaint.h"
	#include "FileDeviceUtils.h"
	#include "Utils.h"
	#include "VoldUtil.h"
	#include "VolumeManager.h"
	#include "model/PrivateVolume.h"

	#include <thread>
	#include <utility>

	#include <aidl/android/hardware/health/storage/BnGarbageCollectCallback.h>
	#include <aidl/android/hardware/health/storage/IStorage.h>
	#include <android-base/chrono_utils.h>
	#include <android-base/file.h>
	#include <android-base/logging.h>
	#include <android-base/stringprintf.h>
	#include <android-base/strings.h>
	#include <android/binder_manager.h>
	#include <android/hardware/health/storage/1.0/IStorage.h>
	#include <fs_mgr.h>
	#include <private/android_filesystem_config.h>
	#include <wakelock/wakelock.h>

	#include <dirent.h>
	#include <fcntl.h>
	#include <sys/mount.h>
	#include <sys/stat.h>
	#include <sys/types.h>
	#include <sys/wait.h>

	using android::base::Basename;
	using android::base::ReadFileToString;
	using android::base::Realpath;
	using android::base::StringPrintf;
	using android::base::Timer;
	using android::base::WriteStringToFile;
	using android::hardware::Return;
	using android::hardware::Void;
	using AStorage = aidl::android::hardware::health::storage::IStorage;
	using ABnGarbageCollectCallback =
	aidl::android::hardware::health::storage::BnGarbageCollectCallback;
	using AResult = aidl::android::hardware::health::storage::Result;
	using HStorage = android::hardware::health::storage::V1_0::IStorage;
	using HGarbageCollectCallback = android::hardware::health::storage::V1_0::IGarbageCollectCallback;
	using HResult = android::hardware::health::storage::V1_0::Result;
	using std::string_literals::operator""s;

	namespace android {
	namespace vold {

	enum class PathTypes {
	kMountPoint = 1,
	kBlkDevice,
	};

	enum class IdleMaintStats {
	kStopped = 1,
	kRunning,
	kAbort,
	};

	static const char* kWakeLock = "IdleMaint";
	static const int DIRTY_SEGMENTS_THRESHOLD = 100;
	/*
	* Timing policy:
	* 1. F2FS_GC = 7 mins
	* 2. Trim = 1 min
	* 3. Dev GC = 2 mins
	*/
	static const int GC_TIMEOUT_SEC = 420;
	static const int DEVGC_TIMEOUT_SEC = 120;
	static const int KBYTES_IN_SEGMENT = 2048;
	static const int MIN_GC_URGENT_SLEEP_TIME = 500;
	static const int ONE_MINUTE_IN_MS = 60000;
	static const int GC_NORMAL_MODE = 0;
	static const int GC_URGENT_MID_MODE = 3;

	static int32_t previousSegmentWrite = 0;

	static IdleMaintStats idle_maint_stat(IdleMaintStats::kStopped);
	static std::condition_variable cv_abort, cv_stop;
	static std::mutex cv_m;

	static void addFromVolumeManager(std::list<std::string>* paths, PathTypes path_type) {
	VolumeManager* vm = VolumeManager::Instance();
	std::list<std::string> privateIds;
	vm->listVolumes(VolumeBase::Type::kPrivate, privateIds);
	for (const auto& id : privateIds) {
	PrivateVolume* vol = static_cast<PrivateVolume*>(vm->findVolume(id).get());
	if (vol != nullptr && vol->getState() == VolumeBase::State::kMounted) {
	if (path_type == PathTypes::kMountPoint) {
	paths->push_back(vol->getPath());
	} else if (path_type == PathTypes::kBlkDevice) {
	std::string gc_path;
	const std::string& fs_type = vol->getFsType();
	if (fs_type == "f2fs" && (Realpath(vol->getRawDmDevPath(), &gc_path) \|\|
	Realpath(vol->getRawDevPath(), &gc_path))) {
	paths->push_back(std::string("/sys/fs/") + fs_type + "/" + Basename(gc_path));
	}
	}
	}
	}
	}

	static void addFromFstab(std::list<std::string>* paths, PathTypes path_type, bool only_data_part) {
	std::string previous_mount_point;
	for (const auto& entry : fstab_default) {
	// Skip raw partitions and swap space.
	if (entry.fs_type == "emmc" \|\| entry.fs_type == "mtd" \|\| entry.fs_type == "swap") {
	continue;
	}
	// Skip read-only filesystems and bind mounts.
	if (entry.flags & (MS_RDONLY \| MS_BIND)) {
	continue;
	}
	// Skip anything without an underlying block device, e.g. virtiofs.
	if (entry.blk_device[0] != '/') {
	continue;
	}
	if (entry.fs_mgr_flags.vold_managed) {
	continue; // Should we trim fat32 filesystems?
	}
	if (entry.fs_mgr_flags.no_trim) {
	continue;
	}

	if (only_data_part && entry.mount_point != "/data") {
	continue;
	}

	// Skip the multi-type partitions, which are required to be following each other.
	// See fs_mgr.c's mount_with_alternatives().
	if (entry.mount_point == previous_mount_point) {
	continue;
	}

	if (path_type == PathTypes::kMountPoint) {
	paths->push_back(entry.mount_point);
	} else if (path_type == PathTypes::kBlkDevice) {
	std::string path;
	if (entry.fs_type == "f2fs" &&
	Realpath(android::vold::BlockDeviceForPath(entry.mount_point + "/"), &path)) {
	paths->push_back("/sys/fs/" + entry.fs_type + "/" + Basename(path));
	}
	}

	previous_mount_point = entry.mount_point;
	}
	}

	void Trim(const android::sp<android::os::IVoldTaskListener>& listener) {
	auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
	if (!wl.has_value()) {
	return;
	}

	// Collect both fstab and vold volumes
	std::list<std::string> paths;
	addFromFstab(&paths, PathTypes::kMountPoint, false);
	addFromVolumeManager(&paths, PathTypes::kMountPoint);

	for (const auto& path : paths) {
	LOG(DEBUG) << "Starting trim of " << path;

	android::os::PersistableBundle extras;
	extras.putString(String16("path"), String16(path.c_str()));

	int fd = open(path.c_str(), O_RDONLY \| O_DIRECTORY \| O_CLOEXEC \| O_NOFOLLOW);
	if (fd < 0) {
	PLOG(WARNING) << "Failed to open " << path;
	if (listener) {
	listener->onStatus(-1, extras);
	}
	continue;
	}

	struct fstrim_range range;
	memset(&range, 0, sizeof(range));
	range.len = ULLONG_MAX;

	nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME);
	if (ioctl(fd, FITRIM, &range)) {
	PLOG(WARNING) << "Trim failed on " << path;
	if (listener) {
	listener->onStatus(-1, extras);
	}
	} else {
	nsecs_t time = systemTime(SYSTEM_TIME_BOOTTIME) - start;
	LOG(INFO) << "Trimmed " << range.len << " bytes on " << path << " in "
	<< nanoseconds_to_milliseconds(time) << "ms";
	extras.putLong(String16("bytes"), range.len);
	extras.putLong(String16("time"), time);
	if (listener) {
	listener->onStatus(0, extras);
	}
	}
	close(fd);
	}

	if (listener) {
	android::os::PersistableBundle extras;
	listener->onFinished(0, extras);
	}

	}

	static bool waitForGc(const std::list<std::string>& paths) {
	std::unique_lock<std::mutex> lk(cv_m, std::defer_lock);
	bool stop = false, aborted = false;
	Timer timer;

	while (!stop && !aborted) {
	stop = true;
	for (const auto& path : paths) {
	std::string dirty_segments;
	if (!ReadFileToString(path + "/dirty_segments", &dirty_segments)) {
	PLOG(WARNING) << "Reading dirty_segments failed in " << path;
	continue;
	}
	if (std::stoi(dirty_segments) > DIRTY_SEGMENTS_THRESHOLD) {
	stop = false;
	break;
	}
	}

	if (stop) break;

	if (timer.duration() >= std::chrono::seconds(GC_TIMEOUT_SEC)) {
	LOG(WARNING) << "GC timeout";
	break;
	}

	lk.lock();
	aborted =
	cv_abort.wait_for(lk, 10s, [] { return idle_maint_stat == IdleMaintStats::kAbort; });
	lk.unlock();
	}

	return aborted;
	}

	static int startGc(const std::list<std::string>& paths) {
	for (const auto& path : paths) {
	LOG(DEBUG) << "Start GC on " << path;
	if (!WriteStringToFile("1", path + "/gc_urgent")) {
	PLOG(WARNING) << "Start GC failed on " << path;
	}
	}
	return android::OK;
	}

	static int stopGc(const std::list<std::string>& paths) {
	for (const auto& path : paths) {
	LOG(DEBUG) << "Stop GC on " << path;
	if (!WriteStringToFile("0", path + "/gc_urgent")) {
	PLOG(WARNING) << "Stop GC failed on " << path;
	}
	}
	return android::OK;
	}

	static std::string getDevSysfsPath() {
	for (const auto& entry : fstab_default) {
	if (!entry.sysfs_path.empty()) {
	return entry.sysfs_path;
	}
	}
	LOG(WARNING) << "Cannot find dev sysfs path";
	return "";
	}

	static void runDevGcFstab(void) {
	std::string path = getDevSysfsPath();
	if (path.empty()) {
	return;
	}

	path = path + "/manual_gc";
	Timer timer;

	LOG(DEBUG) << "Start Dev GC on " << path;
	while (1) {
	std::string require;
	if (!ReadFileToString(path, &require)) {
	PLOG(WARNING) << "Reading manual_gc failed in " << path;
	break;
	}
	require = android::base::Trim(require);
	if (require == "" \|\| require == "off" \|\| require == "disabled") {
	LOG(DEBUG) << "No more to do Dev GC";
	break;
	}

	LOG(DEBUG) << "Trigger Dev GC on " << path;
	if (!WriteStringToFile("1", path)) {
	PLOG(WARNING) << "Start Dev GC failed on " << path;
	break;
	}

	if (timer.duration() >= std::chrono::seconds(DEVGC_TIMEOUT_SEC)) {
	LOG(WARNING) << "Dev GC timeout";
	break;
	}
	sleep(2);
	}
	LOG(DEBUG) << "Stop Dev GC on " << path;
	if (!WriteStringToFile("0", path)) {
	PLOG(WARNING) << "Stop Dev GC failed on " << path;
	}
	return;
	}

	enum class IDL { HIDL, AIDL };
	std::ostream& operator<<(std::ostream& os, IDL idl) {
	return os << (idl == IDL::HIDL ? "HIDL" : "AIDL");
	}

	template <IDL idl, typename Result>
	class GcCallbackImpl {
	protected:
	void onFinishInternal(Result result) {
	std::unique_lock<std::mutex> lock(mMutex);
	mFinished = true;
	mResult = result;
	lock.unlock();
	mCv.notify_all();
	}

	public:
	void wait(uint64_t seconds) {
	std::unique_lock<std::mutex> lock(mMutex);
	mCv.wait_for(lock, std::chrono::seconds(seconds), [this] { return mFinished; });

	if (!mFinished) {
	LOG(WARNING) << "Dev GC on " << idl << " HAL timeout";
	} else if (mResult != Result::SUCCESS) {
	LOG(WARNING) << "Dev GC on " << idl << " HAL failed with " << toString(mResult);
	} else {
	LOG(INFO) << "Dev GC on " << idl << " HAL successful";
	}
	}

	private:
	std::mutex mMutex;
	std::condition_variable mCv;
	bool mFinished{false};
	Result mResult{Result::UNKNOWN_ERROR};
	};

	class AGcCallbackImpl : public ABnGarbageCollectCallback,
	public GcCallbackImpl<IDL::AIDL, AResult> {
	ndk::ScopedAStatus onFinish(AResult result) override {
	onFinishInternal(result);
	return ndk::ScopedAStatus::ok();
	}
	};

	class HGcCallbackImpl : public HGarbageCollectCallback, public GcCallbackImpl<IDL::HIDL, HResult> {
	Return<void> onFinish(HResult result) override {
	onFinishInternal(result);
	return Void();
	}
	};

	template <IDL idl, typename Service, typename GcCallbackImpl, typename GetDescription>
	static void runDevGcOnHal(Service service, GcCallbackImpl cb, GetDescription get_description) {
	LOG(DEBUG) << "Start Dev GC on " << idl << " HAL";
	auto ret = service->garbageCollect(DEVGC_TIMEOUT_SEC, cb);
	if (!ret.isOk()) {
	LOG(WARNING) << "Cannot start Dev GC on " << idl
	<< " HAL: " << std::invoke(get_description, ret);
	return;
	}
	cb->wait(DEVGC_TIMEOUT_SEC);
	}

	static void runDevGc(void) {
	auto aidl_service_name = AStorage::descriptor + "/default"s;
	if (AServiceManager_isDeclared(aidl_service_name.c_str())) {
	ndk::SpAIBinder binder(AServiceManager_waitForService(aidl_service_name.c_str()));
	if (binder.get() != nullptr) {
	std::shared_ptr<AStorage> aidl_service = AStorage::fromBinder(binder);
	if (aidl_service != nullptr) {
	runDevGcOnHal<IDL::AIDL>(aidl_service, ndk::SharedRefBase::make<AGcCallbackImpl>(),
	&ndk::ScopedAStatus::getDescription);
	return;
	}
	}
	LOG(WARNING) << "Device declares " << aidl_service_name
	<< " but it is not running, skip dev GC on AIDL HAL";
	return;
	}
	auto hidl_service = HStorage::getService();
	if (hidl_service != nullptr) {
	runDevGcOnHal<IDL::HIDL>(hidl_service, sp<HGcCallbackImpl>(new HGcCallbackImpl()),
	&Return<void>::description);
	return;
	}
	// fallback to legacy code path
	runDevGcFstab();
	}

	int RunIdleMaint(bool needGC, const android::sp<android::os::IVoldTaskListener>& listener) {
	std::unique_lock<std::mutex> lk(cv_m);
	bool gc_aborted = false;

	if (idle_maint_stat != IdleMaintStats::kStopped) {
	LOG(DEBUG) << "idle maintenance is already running";
	if (listener) {
	android::os::PersistableBundle extras;
	listener->onFinished(0, extras);
	}
	return android::OK;
	}
	idle_maint_stat = IdleMaintStats::kRunning;
	lk.unlock();

	LOG(DEBUG) << "idle maintenance started";

	auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
	if (!wl.has_value()) {
	return android::UNEXPECTED_NULL;
	}

	if (needGC) {
	std::list<std::string> paths;
	addFromFstab(&paths, PathTypes::kBlkDevice, false);
	addFromVolumeManager(&paths, PathTypes::kBlkDevice);

	startGc(paths);

	gc_aborted = waitForGc(paths);

	stopGc(paths);
	}

	lk.lock();
	idle_maint_stat = IdleMaintStats::kStopped;
	lk.unlock();

	cv_stop.notify_one();

	if (!gc_aborted) {
	Trim(nullptr);
	runDevGc();
	}

	if (listener) {
	android::os::PersistableBundle extras;
	listener->onFinished(0, extras);
	}

	LOG(DEBUG) << "idle maintenance completed";

	return android::OK;
	}

	int AbortIdleMaint(const android::sp<android::os::IVoldTaskListener>& listener) {
	auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
	if (!wl.has_value()) {
	return android::UNEXPECTED_NULL;
	}

	std::unique_lock<std::mutex> lk(cv_m);
	if (idle_maint_stat != IdleMaintStats::kStopped) {
	idle_maint_stat = IdleMaintStats::kAbort;
	lk.unlock();
	cv_abort.notify_one();
	lk.lock();
	LOG(DEBUG) << "aborting idle maintenance";
	cv_stop.wait(lk, [] { return idle_maint_stat == IdleMaintStats::kStopped; });
	}
	lk.unlock();

	if (listener) {
	android::os::PersistableBundle extras;
	listener->onFinished(0, extras);
	}

	LOG(DEBUG) << "idle maintenance stopped";

	return android::OK;
	}

	int getLifeTime(const std::string& path) {
	std::string result;

	if (!ReadFileToString(path, &result)) {
	PLOG(WARNING) << "Reading lifetime estimation failed for " << path;
	return -1;
	}
	return std::stoi(result, 0, 16);
	}

	int32_t GetStorageLifeTime() {
	std::string path = getDevSysfsPath();
	if (path.empty()) {
	return -1;
	}

	std::string lifeTimeBasePath = path + "/health_descriptor/life_time_estimation_";

	int32_t lifeTime = getLifeTime(lifeTimeBasePath + "c");
	if (lifeTime != -1) {
	return lifeTime;
	}

	int32_t lifeTimeA = getLifeTime(lifeTimeBasePath + "a");
	int32_t lifeTimeB = getLifeTime(lifeTimeBasePath + "b");
	lifeTime = std::max(lifeTimeA, lifeTimeB);
	if (lifeTime != -1) {
	return lifeTime == 0 ? -1 : lifeTime * 10;
	}
	return -1;
	}

	void SetGCUrgentPace(int32_t neededSegments, int32_t minSegmentThreshold, float dirtyReclaimRate,
	float reclaimWeight, int32_t gcPeriod) {
	std::list<std::string> paths;
	bool needGC = true;

	addFromFstab(&paths, PathTypes::kBlkDevice, true);
	if (paths.empty()) {
	LOG(WARNING) << "There is no valid blk device path for data partition";
	return;
	}

	std::string f2fsSysfsPath = paths.front();
	std::string freeSegmentsPath = f2fsSysfsPath + "/free_segments";
	std::string dirtySegmentsPath = f2fsSysfsPath + "/dirty_segments";
	std::string gcSleepTimePath = f2fsSysfsPath + "/gc_urgent_sleep_time";
	std::string gcUrgentModePath = f2fsSysfsPath + "/gc_urgent";
	std::string freeSegmentsStr, dirtySegmentsStr;

	if (!ReadFileToString(freeSegmentsPath, &freeSegmentsStr)) {
	PLOG(WARNING) << "Reading failed in " << freeSegmentsPath;
	return;
	}

	if (!ReadFileToString(dirtySegmentsPath, &dirtySegmentsStr)) {
	PLOG(WARNING) << "Reading failed in " << dirtySegmentsPath;
	return;
	}

	int32_t freeSegments = std::stoi(freeSegmentsStr);
	int32_t dirtySegments = std::stoi(dirtySegmentsStr);

	neededSegments *= reclaimWeight;
	if (freeSegments >= neededSegments) {
	LOG(INFO) << "Enough free segments: " << freeSegments
	<< ", needed segments: " << neededSegments;
	needGC = false;
	} else if (freeSegments + dirtySegments < minSegmentThreshold) {
	LOG(INFO) << "The sum of free segments: " << freeSegments
	<< ", dirty segments: " << dirtySegments << " is under " << minSegmentThreshold;
	needGC = false;
	}

	if (!needGC) {
	if (!WriteStringToFile(std::to_string(GC_NORMAL_MODE), gcUrgentModePath)) {
	PLOG(WARNING) << "Writing failed in " << gcUrgentModePath;
	}
	return;
	}

	int32_t sleepTime;

	neededSegments -= freeSegments;
	neededSegments = std::min(neededSegments, (int32_t)(dirtySegments * dirtyReclaimRate));
	if (neededSegments == 0) {
	sleepTime = MIN_GC_URGENT_SLEEP_TIME;
	} else {
	sleepTime = gcPeriod * ONE_MINUTE_IN_MS / neededSegments;
	if (sleepTime < MIN_GC_URGENT_SLEEP_TIME) {
	sleepTime = MIN_GC_URGENT_SLEEP_TIME;
	}
	}
	if (!WriteStringToFile(std::to_string(sleepTime), gcSleepTimePath)) {
	PLOG(WARNING) << "Writing failed in " << gcSleepTimePath;
	return;
	}

	if (!WriteStringToFile(std::to_string(GC_URGENT_MID_MODE), gcUrgentModePath)) {
	PLOG(WARNING) << "Writing failed in " << gcUrgentModePath;
	return;
	}

	LOG(INFO) << "Successfully set gc urgent mode: "
	<< "free segments: " << freeSegments << ", reclaim target: " << neededSegments
	<< ", sleep time: " << sleepTime;
	}

	static int32_t getLifeTimeWrite() {
	std::list<std::string> paths;
	addFromFstab(&paths, PathTypes::kBlkDevice, true);
	if (paths.empty()) {
	LOG(WARNING) << "There is no valid blk device path for data partition";
	return -1;
	}

	std::string writeKbytesPath = paths.front() + "/lifetime_write_kbytes";
	std::string writeKbytesStr;
	if (!ReadFileToString(writeKbytesPath, &writeKbytesStr)) {
	PLOG(WARNING) << "Reading failed in " << writeKbytesPath;
	return -1;
	}

	long long writeBytes = std::stoll(writeKbytesStr);
	return writeBytes / KBYTES_IN_SEGMENT;
	}

	void RefreshLatestWrite() {
	int32_t segmentWrite = getLifeTimeWrite();
	if (segmentWrite != -1) {
	previousSegmentWrite = segmentWrite;
	}
	}

	int32_t GetWriteAmount() {
	int32_t currentSegmentWrite = getLifeTimeWrite();
	if (currentSegmentWrite == -1) {
	return -1;
	}

	int32_t writeAmount = currentSegmentWrite - previousSegmentWrite;
	previousSegmentWrite = currentSegmentWrite;
	return writeAmount;
	}

	} // namespace vold
	} // namespace android