MoveTask.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 "MoveTask.h"
 #include "Utils.h"
 #include "VolumeManager.h"
 #include "ResponseCode.h"

 #include <android-base/stringprintf.h>
 #include <android-base/logging.h>
 #include <private/android_filesystem_config.h>
 #include <hardware_legacy/power.h>

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

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

 #define EXEC_BLOCKING 0

 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";

 MoveTask::MoveTask(const std::shared_ptr<VolumeBase>& from,
         const std::shared_ptr<VolumeBase>& to) :
         mFrom(from), mTo(to) {
 }

 MoveTask::~MoveTask() {
 }

 void MoveTask::start() {
     mThread = std::thread(&MoveTask::run, this);
 }

 static void notifyProgress(int progress) {
     VolumeManager::Instance()->getBroadcaster()->sendBroadcast(ResponseCode::MoveStatus,
             StringPrintf("%d", progress).c_str(), false);
 }

 static status_t pushBackContents(const std::string& path, std::vector<std::string>& cmd,
         bool addWildcard) {
     DIR* dir = opendir(path.c_str());
     if (dir == NULL) {
         return -1;
     }
     bool found = false;
     struct dirent* ent;
     while ((ent = readdir(dir)) != NULL) {
         if ((!strcmp(ent->d_name, ".")) || (!strcmp(ent->d_name, ".."))) {
             continue;
         }
         if (addWildcard) {
             cmd.push_back(StringPrintf("%s/%s/*", path.c_str(), ent->d_name));
         } else {
             cmd.push_back(StringPrintf("%s/%s", path.c_str(), ent->d_name));
         }
         found = true;
     }
     closedir(dir);
     return found ? OK : -1;
 }

 static status_t execRm(const std::string& path, int startProgress, int stepProgress) {
     notifyProgress(startProgress);

     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, true) != OK) {
         LOG(WARNING) << "No contents in " << path;
         return OK;
     }

 #if EXEC_BLOCKING
     return ForkExecvp(cmd);
 #else
     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));
     }
     return -1;
 #endif
 }

 static status_t execCp(const std::string& fromPath, const std::string& toPath,
         int startProgress, int stepProgress) {
     notifyProgress(startProgress);

     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, false) != OK) {
         LOG(WARNING) << "No contents in " << fromPath;
         return OK;
     }
     cmd.push_back(toPath.c_str());

 #if EXEC_BLOCKING
     return ForkExecvp(cmd);
 #else
     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));
     }
     return -1;
 #endif
 }

 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();
 }

 void MoveTask::run() {
     acquire_wake_lock(PARTIAL_WAKE_LOCK, kWakeLock);

     std::string fromPath;
     std::string toPath;

     // TODO: add support for public volumes
     if (mFrom->getType() != VolumeBase::Type::kEmulated) goto fail;
     if (mTo->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(mFrom);
         bringOffline(mTo);
     }

     fromPath = mFrom->getInternalPath();
     toPath = mTo->getInternalPath();

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

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

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

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

     notifyProgress(kMoveSucceeded);
     release_wake_lock(kWakeLock);
     return;

 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);
 fail:
     {
         std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
         bringOnline(mFrom);
         bringOnline(mTo);
     }
     notifyProgress(kMoveFailedInternalError);
     release_wake_lock(kWakeLock);
     return;
 }

 }  // 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 "MoveTask.h"
	#include "Utils.h"
	#include "VolumeManager.h"
	#include "ResponseCode.h"

	#include <android-base/stringprintf.h>
	#include <android-base/logging.h>
	#include <private/android_filesystem_config.h>
	#include <hardware_legacy/power.h>

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

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

	#define EXEC_BLOCKING 0

	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";

	MoveTask::MoveTask(const std::shared_ptr<VolumeBase>& from,
	const std::shared_ptr<VolumeBase>& to) :
	mFrom(from), mTo(to) {
	}

	MoveTask::~MoveTask() {
	}

	void MoveTask::start() {
	mThread = std::thread(&MoveTask::run, this);
	}

	static void notifyProgress(int progress) {
	VolumeManager::Instance()->getBroadcaster()->sendBroadcast(ResponseCode::MoveStatus,
	StringPrintf("%d", progress).c_str(), false);
	}

	static status_t pushBackContents(const std::string& path, std::vector<std::string>& cmd,
	bool addWildcard) {
	DIR* dir = opendir(path.c_str());
	if (dir == NULL) {
	return -1;
	}
	bool found = false;
	struct dirent* ent;
	while ((ent = readdir(dir)) != NULL) {
	if ((!strcmp(ent->d_name, ".")) \|\| (!strcmp(ent->d_name, ".."))) {
	continue;
	}
	if (addWildcard) {
	cmd.push_back(StringPrintf("%s/%s/*", path.c_str(), ent->d_name));
	} else {
	cmd.push_back(StringPrintf("%s/%s", path.c_str(), ent->d_name));
	}
	found = true;
	}
	closedir(dir);
	return found ? OK : -1;
	}

	static status_t execRm(const std::string& path, int startProgress, int stepProgress) {
	notifyProgress(startProgress);

	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, true) != OK) {
	LOG(WARNING) << "No contents in " << path;
	return OK;
	}

	#if EXEC_BLOCKING
	return ForkExecvp(cmd);
	#else
	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));
	}
	return -1;
	#endif
	}

	static status_t execCp(const std::string& fromPath, const std::string& toPath,
	int startProgress, int stepProgress) {
	notifyProgress(startProgress);

	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, false) != OK) {
	LOG(WARNING) << "No contents in " << fromPath;
	return OK;
	}
	cmd.push_back(toPath.c_str());

	#if EXEC_BLOCKING
	return ForkExecvp(cmd);
	#else
	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));
	}
	return -1;
	#endif
	}

	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();
	}

	void MoveTask::run() {
	acquire_wake_lock(PARTIAL_WAKE_LOCK, kWakeLock);

	std::string fromPath;
	std::string toPath;

	// TODO: add support for public volumes
	if (mFrom->getType() != VolumeBase::Type::kEmulated) goto fail;
	if (mTo->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(mFrom);
	bringOffline(mTo);
	}

	fromPath = mFrom->getInternalPath();
	toPath = mTo->getInternalPath();

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

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

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

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

	notifyProgress(kMoveSucceeded);
	release_wake_lock(kWakeLock);
	return;

	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);
	fail:
	{
	std::lock_guard<std::mutex> lock(VolumeManager::Instance()->getLock());
	bringOnline(mFrom);
	bringOnline(mTo);
	}
	notifyProgress(kMoveFailedInternalError);
	release_wake_lock(kWakeLock);
	return;
	}

	} // namespace vold
	} // namespace android