| /* |
| * Copyright (C) 2018 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. |
| */ |
| package com.android.car.storagemonitoring; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.car.storagemonitoring.LifetimeWriteInfo; |
| import android.util.Log; |
| import com.android.internal.annotations.VisibleForTesting; |
| import java.io.File; |
| import java.io.IOException; |
| import java.nio.file.Files; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Objects; |
| |
| /** |
| * <p>Loads lifetime write data for mounted filesystems via sysfs.</p> |
| * |
| * <p>ext4 and f2fs currently offer this information via |
| * /sys/fs/<i>type</i>/<i>partition</i>/lifetime_write_kbytes VFS entry points.</p> |
| */ |
| public class SysfsLifetimeWriteInfoProvider implements LifetimeWriteInfoProvider { |
| private static final String TAG = SysfsLifetimeWriteInfoProvider.class.getSimpleName(); |
| |
| private static final String DEFAULT_PATH = "/sys/fs/"; |
| private static final String[] KNOWN_FILESYSTEMS = new String[] { |
| "ext4", |
| "f2fs" |
| }; |
| private static final String FILENAME = "lifetime_write_kbytes"; |
| |
| private final File mWriteInfosPath; |
| |
| public SysfsLifetimeWriteInfoProvider() { |
| this(new File(DEFAULT_PATH)); |
| } |
| |
| @VisibleForTesting |
| SysfsLifetimeWriteInfoProvider(File writeInfosPath) { |
| mWriteInfosPath = writeInfosPath; |
| } |
| |
| @Nullable |
| private LifetimeWriteInfo tryParse(File dir) { |
| File writefile = new File(dir, FILENAME); |
| if (!writefile.exists() || !writefile.isFile()) { |
| Log.d(TAG, writefile + " not a valid source of lifetime writes"); |
| return null; |
| } |
| List<String> datalines; |
| try { |
| datalines = Files.readAllLines(writefile.toPath()); |
| } catch (IOException e) { |
| Log.e(TAG, "unable to read write info from " + writefile, e); |
| return null; |
| } |
| if (datalines == null || datalines.size() != 1) { |
| Log.e(TAG, "unable to read valid write info from " + writefile); |
| return null; |
| } |
| String data = datalines.get(0); |
| try { |
| long writtenBytes = 1024L * Long.parseLong(data); |
| if (writtenBytes < 0) { |
| Log.e(TAG, "file at location " + writefile + |
| " contained a negative data amount " + data + ". Ignoring."); |
| return null; |
| } else { |
| return new LifetimeWriteInfo( |
| dir.getName(), |
| dir.getParentFile().getName(), |
| writtenBytes); |
| } |
| } catch (NumberFormatException e) { |
| Log.e(TAG, "unable to read valid write info from " + writefile, e); |
| return null; |
| } |
| } |
| |
| @Override |
| @NonNull |
| public LifetimeWriteInfo[] load() { |
| List<LifetimeWriteInfo> writeInfos = new ArrayList<>(); |
| |
| for (String fstype : KNOWN_FILESYSTEMS) { |
| File fspath = new File(mWriteInfosPath, fstype); |
| if (!fspath.exists() || !fspath.isDirectory()) continue; |
| Arrays.stream(fspath.listFiles(File::isDirectory)) |
| .map(this::tryParse) |
| .filter(Objects::nonNull) |
| .forEach(writeInfos::add); |
| } |
| |
| return writeInfos.toArray(new LifetimeWriteInfo[0]); |
| } |
| } |