MoveStorage.cpp - platform/system/vold - Git at Google

 /*
  * 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 "MoveStorage.h"
 #include "Utils.h"
 #include "VolumeManager.h"

 #include <android-base/logging.h>
 #include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <private/android_filesystem_config.h>
 #include <wakelock/wakelock.h>

 #include <thread>

 #include <dirent.h>
 #include <sys/wait.h>

 #define CONSTRAIN(amount, low, high) \
     ((amount) < (low) ? (low) : ((amount) > (high) ? (high) : (amount)))

 static const char* kPropBlockingExec = "persist.sys.blocking_exec";

 using android::base::StringPrintf;

 namespace android {
 namespace vold {

 // TODO: keep in sync with PackageManager
 static const int kMoveSucceeded = -100;
 static const int kMoveFailedInternalError = -6;

 static const char* kCpPath = "/system/bin/cp";
 static const char* kRmPath = "/system/bin/rm";

 static const char* kWakeLock = "MoveTask";

 static void notifyProgress(int progress,
                            const android::sp<android::os::IVoldTaskListener>& listener) {
     if (listener) {
         android::os::PersistableBundle extras;
         listener->onStatus(progress, extras);
     }
 }

 static bool pushBackContents(const std::string& path, std::vector<std::string>& cmd,
                              int searchLevels) {
     if (searchLevels == 0) {
         cmd.emplace_back(path);
         return true;
     }
     auto dirp = std::unique_ptr<DIR, int (*)(DIR*)>(opendir(path.c_str()), closedir);
     if (!dirp) {
         PLOG(ERROR) << "Unable to open directory: " << path;
         return false;
     }
     bool found = false;
     struct dirent* ent;
     while ((ent = readdir(dirp.get())) != NULL) {
         if (IsDotOrDotDot(*ent)) continue;
         auto subdir = path + "/" + ent->d_name;
         found |= pushBackContents(subdir, cmd, searchLevels - 1);
     }
     return found;
 }

 static status_t execRm(const std::string& path, int startProgress, int stepProgress,
                        const android::sp<android::os::IVoldTaskListener>& listener) {
     notifyProgress(startProgress, listener);

     uint64_t expectedBytes = GetTreeBytes(path);
     uint64_t startFreeBytes = GetFreeBytes(path);

     std::vector<std::string> cmd;
     cmd.push_back(kRmPath);
     cmd.push_back("-f"); /* force: remove without confirmation, no error if it doesn't exist */
     cmd.push_back("-R"); /* recursive: remove directory contents */
     if (!pushBackContents(path, cmd, 2)) {
         LOG(WARNING) << "No contents in " << path;
         return OK;
     }

     if (android::base::GetBoolProperty(kPropBlockingExec, false)) {
         return ForkExecvp(cmd);
     }

     pid_t pid = ForkExecvpAsync(cmd);
     if (pid == -1) return -1;

     int status;
     while (true) {
         if (waitpid(pid, &status, WNOHANG) == pid) {
             if (WIFEXITED(status)) {
                 LOG(DEBUG) << "Finished rm with status " << WEXITSTATUS(status);
                 return (WEXITSTATUS(status) == 0) ? OK : -1;
             } else {
                 break;
             }
         }

         sleep(1);
         uint64_t deltaFreeBytes = GetFreeBytes(path) - startFreeBytes;
         notifyProgress(
             startProgress +
                 CONSTRAIN((int)((deltaFreeBytes * stepProgress) / expectedBytes), 0, stepProgress),
             listener);
     }
     return -1;
 }

 static status_t execCp(const std::string& fromPath, const std::string& toPath, int startProgress,
                        int stepProgress,
                        const android::sp<android::os::IVoldTaskListener>& listener) {
     notifyProgress(startProgress, listener);

     uint64_t expectedBytes = GetTreeBytes(fromPath);
     uint64_t startFreeBytes = GetFreeBytes(toPath);

     if (expectedBytes > startFreeBytes) {
         LOG(ERROR) << "Data size " << expectedBytes << " is too large to fit in free space "
                    << startFreeBytes;
         return -1;
     }

     std::vector<std::string> cmd;
     cmd.push_back(kCpPath);
     cmd.push_back("-p"); /* preserve timestamps, ownership, and permissions */
     cmd.push_back("-R"); /* recurse into subdirectories (DEST must be a directory) */
     cmd.push_back("-P"); /* Do not follow symlinks [default] */
     cmd.push_back("-d"); /* don't dereference symlinks */
     if (!pushBackContents(fromPath, cmd, 1)) {
         LOG(WARNING) << "No contents in " << fromPath;
         return OK;
     }
     cmd.push_back(toPath.c_str());

     if (android::base::GetBoolProperty(kPropBlockingExec, false)) {
         return ForkExecvp(cmd);
     }

     pid_t pid = ForkExecvpAsync(cmd);
     if (pid == -1) return -1;

     int status;
     while (true) {
         if (waitpid(pid, &status, WNOHANG) == pid) {
             if (WIFEXITED(status)) {
                 LOG(DEBUG) << "Finished cp with status " << WEXITSTATUS(status);
                 return (WEXITSTATUS(status) == 0) ? OK : -1;
             } else {
                 break;
             }
         }

         sleep(1);
         uint64_t deltaFreeBytes = startFreeBytes - GetFreeBytes(toPath);
         notifyProgress(
             startProgress +
                 CONSTRAIN((int)((deltaFreeBytes * stepProgress) / expectedBytes), 0, stepProgress),
             listener);
     }
     return -1;
 }

 static void bringOffline(const std::shared_ptr<VolumeBase>& vol) {
     vol->destroy();
     vol->setSilent(true);
     vol->create();
     vol->setMountFlags(0);
     vol->mount();
 }

 static void bringOnline(const std::shared_ptr<VolumeBase>& vol) {
     vol->destroy();
     vol->setSilent(false);
     vol->create();
 }

 static status_t moveStorageInternal(const std::shared_ptr<VolumeBase>& from,
                                     const std::shared_ptr<VolumeBase>& to,
                                     const android::sp<android::os::IVoldTaskListener>& listener) {
     std::string fromPath;
     std::string toPath;

     // TODO: add support for public volumes
     if (from->getType() != VolumeBase::Type::kEmulated) goto fail;
     if (to->getType() != VolumeBase::Type::kEmulated) goto fail;

     // Step 1: tear down volumes and mount silently without making
     // visible to userspace apps
     {
         std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
         bringOffline(from);
         bringOffline(to);
     }

     fromPath = from->getInternalPath();
     toPath = to->getInternalPath();

     // Step 2: clean up any stale data
     if (execRm(toPath, 10, 10, listener) != OK) {
         goto fail;
     }

     // Step 3: perform actual copy
     if (execCp(fromPath, toPath, 20, 60, listener) != OK) {
         goto copy_fail;
     }

     // NOTE: MountService watches for this magic value to know
     // that move was successful
     notifyProgress(82, listener);
     {
         std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
         bringOnline(from);
         bringOnline(to);
     }

     // Step 4: clean up old data
     if (execRm(fromPath, 85, 15, listener) != OK) {
         goto fail;
     }

     notifyProgress(kMoveSucceeded, listener);
     return OK;

 copy_fail:
     // if we failed to copy the data we should not leave it laying around
     // in target location. Do not check return value, we can not do any
     // useful anyway.
     execRm(toPath, 80, 1, listener);
 fail:
     // clang-format off
     {
         std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
         bringOnline(from);
         bringOnline(to);
     }
     // clang-format on
     notifyProgress(kMoveFailedInternalError, listener);
     return -1;
 }

 void MoveStorage(const std::shared_ptr<VolumeBase>& from, const std::shared_ptr<VolumeBase>& to,
                  const android::sp<android::os::IVoldTaskListener>& listener) {
     auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
     if (!wl.has_value()) {
         return;
     }

     android::os::PersistableBundle extras;
     status_t res = moveStorageInternal(from, to, listener);
     if (listener) {
         listener->onFinished(res, extras);
     }
 }

 }  // 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 "MoveStorage.h"
	#include "Utils.h"
	#include "VolumeManager.h"

	#include <android-base/logging.h>
	#include <android-base/properties.h>
	#include <android-base/stringprintf.h>
	#include <private/android_filesystem_config.h>
	#include <wakelock/wakelock.h>

	#include <thread>

	#include <dirent.h>
	#include <sys/wait.h>

	#define CONSTRAIN(amount, low, high) \
	((amount) < (low) ? (low) : ((amount) > (high) ? (high) : (amount)))

	static const char* kPropBlockingExec = "persist.sys.blocking_exec";

	using android::base::StringPrintf;

	namespace android {
	namespace vold {

	// TODO: keep in sync with PackageManager
	static const int kMoveSucceeded = -100;
	static const int kMoveFailedInternalError = -6;

	static const char* kCpPath = "/system/bin/cp";
	static const char* kRmPath = "/system/bin/rm";

	static const char* kWakeLock = "MoveTask";

	static void notifyProgress(int progress,
	const android::sp<android::os::IVoldTaskListener>& listener) {
	if (listener) {
	android::os::PersistableBundle extras;
	listener->onStatus(progress, extras);
	}
	}

	static bool pushBackContents(const std::string& path, std::vector<std::string>& cmd,
	int searchLevels) {
	if (searchLevels == 0) {
	cmd.emplace_back(path);
	return true;
	}
	auto dirp = std::unique_ptr<DIR, int ()(DIR)>(opendir(path.c_str()), closedir);
	if (!dirp) {
	PLOG(ERROR) << "Unable to open directory: " << path;
	return false;
	}
	bool found = false;
	struct dirent* ent;
	while ((ent = readdir(dirp.get())) != NULL) {
	if (IsDotOrDotDot(*ent)) continue;
	auto subdir = path + "/" + ent->d_name;
	found \|= pushBackContents(subdir, cmd, searchLevels - 1);
	}
	return found;
	}

	static status_t execRm(const std::string& path, int startProgress, int stepProgress,
	const android::sp<android::os::IVoldTaskListener>& listener) {
	notifyProgress(startProgress, listener);

	uint64_t expectedBytes = GetTreeBytes(path);
	uint64_t startFreeBytes = GetFreeBytes(path);

	std::vector<std::string> cmd;
	cmd.push_back(kRmPath);
	cmd.push_back("-f"); /* force: remove without confirmation, no error if it doesn't exist */
	cmd.push_back("-R"); /* recursive: remove directory contents */
	if (!pushBackContents(path, cmd, 2)) {
	LOG(WARNING) << "No contents in " << path;
	return OK;
	}

	if (android::base::GetBoolProperty(kPropBlockingExec, false)) {
	return ForkExecvp(cmd);
	}

	pid_t pid = ForkExecvpAsync(cmd);
	if (pid == -1) return -1;

	int status;
	while (true) {
	if (waitpid(pid, &status, WNOHANG) == pid) {
	if (WIFEXITED(status)) {
	LOG(DEBUG) << "Finished rm with status " << WEXITSTATUS(status);
	return (WEXITSTATUS(status) == 0) ? OK : -1;
	} else {
	break;
	}
	}

	sleep(1);
	uint64_t deltaFreeBytes = GetFreeBytes(path) - startFreeBytes;
	notifyProgress(
	startProgress +
	CONSTRAIN((int)((deltaFreeBytes * stepProgress) / expectedBytes), 0, stepProgress),
	listener);
	}
	return -1;
	}

	static status_t execCp(const std::string& fromPath, const std::string& toPath, int startProgress,
	int stepProgress,
	const android::sp<android::os::IVoldTaskListener>& listener) {
	notifyProgress(startProgress, listener);

	uint64_t expectedBytes = GetTreeBytes(fromPath);
	uint64_t startFreeBytes = GetFreeBytes(toPath);

	if (expectedBytes > startFreeBytes) {
	LOG(ERROR) << "Data size " << expectedBytes << " is too large to fit in free space "
	<< startFreeBytes;
	return -1;
	}

	std::vector<std::string> cmd;
	cmd.push_back(kCpPath);
	cmd.push_back("-p"); /* preserve timestamps, ownership, and permissions */
	cmd.push_back("-R"); /* recurse into subdirectories (DEST must be a directory) */
	cmd.push_back("-P"); /* Do not follow symlinks [default] */
	cmd.push_back("-d"); /* don't dereference symlinks */
	if (!pushBackContents(fromPath, cmd, 1)) {
	LOG(WARNING) << "No contents in " << fromPath;
	return OK;
	}
	cmd.push_back(toPath.c_str());

	if (android::base::GetBoolProperty(kPropBlockingExec, false)) {
	return ForkExecvp(cmd);
	}

	pid_t pid = ForkExecvpAsync(cmd);
	if (pid == -1) return -1;

	int status;
	while (true) {
	if (waitpid(pid, &status, WNOHANG) == pid) {
	if (WIFEXITED(status)) {
	LOG(DEBUG) << "Finished cp with status " << WEXITSTATUS(status);
	return (WEXITSTATUS(status) == 0) ? OK : -1;
	} else {
	break;
	}
	}

	sleep(1);
	uint64_t deltaFreeBytes = startFreeBytes - GetFreeBytes(toPath);
	notifyProgress(
	startProgress +
	CONSTRAIN((int)((deltaFreeBytes * stepProgress) / expectedBytes), 0, stepProgress),
	listener);
	}
	return -1;
	}

	static void bringOffline(const std::shared_ptr<VolumeBase>& vol) {
	vol->destroy();
	vol->setSilent(true);
	vol->create();
	vol->setMountFlags(0);
	vol->mount();
	}

	static void bringOnline(const std::shared_ptr<VolumeBase>& vol) {
	vol->destroy();
	vol->setSilent(false);
	vol->create();
	}

	static status_t moveStorageInternal(const std::shared_ptr<VolumeBase>& from,
	const std::shared_ptr<VolumeBase>& to,
	const android::sp<android::os::IVoldTaskListener>& listener) {
	std::string fromPath;
	std::string toPath;

	// TODO: add support for public volumes
	if (from->getType() != VolumeBase::Type::kEmulated) goto fail;
	if (to->getType() != VolumeBase::Type::kEmulated) goto fail;

	// Step 1: tear down volumes and mount silently without making
	// visible to userspace apps
	{
	std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
	bringOffline(from);
	bringOffline(to);
	}

	fromPath = from->getInternalPath();
	toPath = to->getInternalPath();

	// Step 2: clean up any stale data
	if (execRm(toPath, 10, 10, listener) != OK) {
	goto fail;
	}

	// Step 3: perform actual copy
	if (execCp(fromPath, toPath, 20, 60, listener) != OK) {
	goto copy_fail;
	}

	// NOTE: MountService watches for this magic value to know
	// that move was successful
	notifyProgress(82, listener);
	{
	std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
	bringOnline(from);
	bringOnline(to);
	}

	// Step 4: clean up old data
	if (execRm(fromPath, 85, 15, listener) != OK) {
	goto fail;
	}

	notifyProgress(kMoveSucceeded, listener);
	return OK;

	copy_fail:
	// if we failed to copy the data we should not leave it laying around
	// in target location. Do not check return value, we can not do any
	// useful anyway.
	execRm(toPath, 80, 1, listener);
	fail:
	// clang-format off
	{
	std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
	bringOnline(from);
	bringOnline(to);
	}
	// clang-format on
	notifyProgress(kMoveFailedInternalError, listener);
	return -1;
	}

	void MoveStorage(const std::shared_ptr<VolumeBase>& from, const std::shared_ptr<VolumeBase>& to,
	const android::sp<android::os::IVoldTaskListener>& listener) {
	auto wl = android::wakelock::WakeLock::tryGet(kWakeLock);
	if (!wl.has_value()) {
	return;
	}

	android::os::PersistableBundle extras;
	status_t res = moveStorageInternal(from, to, listener);
	if (listener) {
	listener->onFinished(res, extras);
	}
	}

	} // namespace vold
	} // namespace android