platform_system_vold/EmulatedVolume.cpp
Jeff Sharkey 8d15cb9828 Report internal path for public volumes.
Used by framework to bypass FUSE daemon overhead in some cases.

Bug: 21017105
Change-Id: I2f3ae70607417fc4cd2c970cb17cf3afa2f42613
2015-05-13 12:36:48 -07:00

108 lines
2.9 KiB
C++

/*
* 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 "EmulatedVolume.h"
#include "Utils.h"
#include <base/stringprintf.h>
#include <base/logging.h>
#include <cutils/fs.h>
#include <private/android_filesystem_config.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
using android::base::StringPrintf;
namespace android {
namespace vold {
static const char* kFusePath = "/system/bin/sdcard";
EmulatedVolume::EmulatedVolume(const std::string& rawPath) :
VolumeBase(Type::kEmulated), mFusePid(0) {
setId("emulated");
mFusePath = "/storage/emulated";
mRawPath = rawPath;
}
EmulatedVolume::EmulatedVolume(const std::string& rawPath, dev_t device,
const std::string& fsUuid) : VolumeBase(Type::kEmulated), mFusePid(0) {
setId(StringPrintf("emulated:%u,%u", major(device), minor(device)));
mFusePath = StringPrintf("/storage/%s", fsUuid.c_str());
mRawPath = rawPath;
}
EmulatedVolume::~EmulatedVolume() {
}
status_t EmulatedVolume::doMount() {
if (fs_prepare_dir(mFusePath.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create mount point " << mFusePath;
return -errno;
}
setInternalPath(mRawPath);
setPath(mFusePath);
if (!(mFusePid = fork())) {
// TODO: protect when not mounted as visible
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
"-l",
mRawPath.c_str(),
mFusePath.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
PLOG(DEBUG) << "FUSE exiting";
_exit(1);
}
if (mFusePid == -1) {
PLOG(ERROR) << getId() << " failed to fork";
return -errno;
}
return OK;
}
status_t EmulatedVolume::doUnmount() {
if (mFusePid > 0) {
kill(mFusePid, SIGTERM);
TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
mFusePid = 0;
}
ForceUnmount(mFusePath);
ForceUnmount(mRawPath);
if (TEMP_FAILURE_RETRY(rmdir(mFusePath.c_str()))) {
PLOG(ERROR) << getId() << " failed to rmdir mount point " << mFusePath;
return -errno;
}
return OK;
}
} // namespace vold
} // namespace android