platform_system_vold/model/ObbVolume.cpp
Jeff Sharkey 11c2d380a7 Move even more vold commands over to Binder.
This moves fstrim, obb and appfuse commands over to the new Binder
interface.  This change also separates creating/destroying and
mounting/unmounting of OBB volumes, which means they finally flow
nicely into the modern VolumeInfo/VolumeBase design.

We now generate unique identifiers for all OBB volumes, instead of
using a shady MD5 hash.

Change all "loop" and "dm" devices to tag the kernel resources with
a vold-specific prefix so that we can clean them up if vold crashes;
there are new destroyAll() methods that handle this cleanup.

Move appfuse mounting/unmounting into VolumeManager so it can be
shared.  Move various model objects into a separate directory to
tidy things up.

Test: cts-tradefed run commandAndExit cts-dev -m CtsOsTestCases -t android.os.storage.cts.StorageManagerTest
Bug: 13758960
Change-Id: I7294e32b3fb6efe07cb3b77bd20166e70b66958f
2017-09-11 18:44:17 -06:00

130 lines
3.5 KiB
C++

/*
* Copyright (C) 2017 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 "fs/Vfat.h"
#include "Devmapper.h"
#include "Loop.h"
#include "ObbVolume.h"
#include "Utils.h"
#include "VoldUtil.h"
#include <android-base/logging.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.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/sysmacros.h>
#include <sys/wait.h>
using android::base::StringPrintf;
using android::base::unique_fd;
namespace android {
namespace vold {
ObbVolume::ObbVolume(int id, const std::string& sourcePath, const std::string& sourceKey,
gid_t ownerGid) : VolumeBase(Type::kObb) {
setId(StringPrintf("obb:%d", id));
mSourcePath = sourcePath;
mSourceKey = sourceKey;
mOwnerGid = ownerGid;
}
ObbVolume::~ObbVolume() {
}
status_t ObbVolume::doCreate() {
if (Loop::create(mSourcePath, mLoopPath)) {
PLOG(ERROR) << getId() << " failed to create loop";
return -1;
}
if (!mSourceKey.empty()) {
unsigned long nr_sec = 0;
{
unique_fd loop_fd(open(mLoopPath.c_str(), O_RDWR | O_CLOEXEC));
if (loop_fd.get() == -1) {
PLOG(ERROR) << getId() << " failed to open loop";
return -1;
}
get_blkdev_size(loop_fd.get(), &nr_sec);
if (nr_sec == 0) {
PLOG(ERROR) << getId() << " failed to get loop size";
return -1;
}
}
char tmp[PATH_MAX];
if (Devmapper::create(getId().c_str(), mLoopPath.c_str(), mSourceKey.c_str(), nr_sec,
tmp, PATH_MAX)) {
PLOG(ERROR) << getId() << " failed to create dm";
return -1;
}
mDmPath = tmp;
mMountPath = mDmPath;
} else {
mMountPath = mLoopPath;
}
return OK;
}
status_t ObbVolume::doDestroy() {
if (!mDmPath.empty() && Devmapper::destroy(getId().c_str())) {
PLOG(WARNING) << getId() << " failed to destroy dm";
}
if (!mLoopPath.empty() && Loop::destroyByDevice(mLoopPath.c_str())) {
PLOG(WARNING) << getId() << " failed to destroy loop";
}
mDmPath.clear();
mLoopPath.clear();
return OK;
}
status_t ObbVolume::doMount() {
auto path = StringPrintf("/mnt/obb/%s", getId().c_str());
setPath(path);
if (fs_prepare_dir(path.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create mount point";
return -1;
}
if (android::vold::vfat::Mount(mMountPath, path,
true, false, true, 0, mOwnerGid, 0227, false)) {
PLOG(ERROR) << getId() << " failed to mount";
return -1;
}
return OK;
}
status_t ObbVolume::doUnmount() {
auto path = getPath();
KillProcessesUsingPath(path);
ForceUnmount(path);
rmdir(path.c_str());
return OK;
}
} // namespace vold
} // namespace android