Philip Cuadra | 7bd0fdd | 2016-04-28 15:26:49 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2016 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package com.android.server; |
| 18 | |
| 19 | import android.content.Context; |
| 20 | import android.content.pm.PackageManager; |
| 21 | import android.content.res.Resources; |
| 22 | import android.util.EventLog; |
| 23 | import android.util.Slog; |
| 24 | import android.os.Binder; |
| 25 | import android.os.Build; |
| 26 | import android.system.ErrnoException; |
| 27 | import android.system.Os; |
| 28 | import android.system.OsConstants; |
| 29 | import android.system.StructStat; |
| 30 | |
| 31 | import java.util.ArrayList; |
| 32 | import java.io.FileDescriptor; |
| 33 | import java.io.FileOutputStream; |
| 34 | import java.io.IOException; |
| 35 | import java.io.PrintWriter; |
| 36 | |
| 37 | /** |
| 38 | * <p>PinnerService pins important files for key processes in memory.</p> |
| 39 | * <p>Files to pin are specified in the config_defaultPinnerServiceFiles |
| 40 | * overlay. </p> |
| 41 | */ |
| 42 | public final class PinnerService extends SystemService { |
| 43 | private static final boolean DEBUG = false; |
| 44 | private static final String TAG = "PinnerService"; |
| 45 | |
| 46 | private final Context mContext; |
| 47 | private final ArrayList<String> mPinnedFiles = new ArrayList<String>(); |
| 48 | |
| 49 | private BinderService mBinderService; |
| 50 | |
| 51 | |
| 52 | public PinnerService(Context context) { |
| 53 | super(context); |
| 54 | |
| 55 | mContext = context; |
| 56 | |
| 57 | } |
| 58 | |
| 59 | @Override |
| 60 | public void onStart() { |
| 61 | Slog.e(TAG, "Starting PinnerService"); |
| 62 | |
| 63 | mBinderService = new BinderService(); |
| 64 | publishBinderService("pinner", mBinderService); |
| 65 | |
| 66 | // Files to pin come from the overlay and can be specified per-device config |
| 67 | // Continue trying to pin remaining files even if there is a failure |
| 68 | String[] filesToPin = mContext.getResources().getStringArray(com.android.internal.R.array.config_defaultPinnerServiceFiles); |
| 69 | for (int i = 0; i < filesToPin.length; i++){ |
| 70 | boolean success = pinFile(filesToPin[i], 0, 0); |
| 71 | if (success == true) { |
| 72 | mPinnedFiles.add(filesToPin[i]); |
| 73 | Slog.i(TAG, "Pinned file = " + filesToPin[i]); |
| 74 | } else { |
| 75 | Slog.e(TAG, "Failed to pin file = " + filesToPin[i]); |
| 76 | } |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | // mlock length bytes of fileToPin in memory, starting at offset |
| 81 | // length == 0 means pin from offset to end of file |
| 82 | private boolean pinFile(String fileToPin, long offset, long length) { |
| 83 | FileDescriptor fd = new FileDescriptor(); |
| 84 | try { |
| 85 | fd = Os.open(fileToPin, OsConstants.O_RDONLY | OsConstants.O_CLOEXEC | OsConstants.O_NOFOLLOW, OsConstants.O_RDONLY); |
| 86 | |
| 87 | StructStat sb = Os.fstat(fd); |
| 88 | |
| 89 | if (offset + length > sb.st_size) { |
| 90 | Os.close(fd); |
| 91 | return false; |
| 92 | } |
| 93 | |
| 94 | if (length == 0) { |
| 95 | length = sb.st_size - offset; |
| 96 | } |
| 97 | |
| 98 | long address = Os.mmap(0, length, OsConstants.PROT_READ, OsConstants.MAP_PRIVATE, fd, offset); |
| 99 | Os.close(fd); |
| 100 | |
| 101 | Os.mlock(address, length); |
| 102 | |
| 103 | return true; |
| 104 | } catch (ErrnoException e) { |
| 105 | Slog.e(TAG, "Failed to pin file " + fileToPin + " with error " + e.getMessage()); |
| 106 | if(fd.valid()) { |
| 107 | try { Os.close(fd); } |
| 108 | catch (ErrnoException eClose) {Slog.e(TAG, "Failed to close fd, error = " + eClose.getMessage());} |
| 109 | } |
| 110 | return false; |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | |
| 115 | private final class BinderService extends Binder { |
| 116 | @Override |
| 117 | protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) { |
| 118 | mContext.enforceCallingOrSelfPermission(android.Manifest.permission.DUMP, TAG); |
| 119 | pw.println("Pinned Files:"); |
| 120 | for (int i = 0; i < mPinnedFiles.size(); i++) { |
| 121 | pw.println(mPinnedFiles.get(i)); |
| 122 | } |
| 123 | } |
| 124 | } |
| 125 | } |