1/* 2 * Copyright (C) 2012 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#include <stdio.h> 18#include <stdlib.h> 19#include <fcntl.h> 20#include <unistd.h> 21#include <errno.h> 22#include <string.h> 23#include <dirent.h> 24#include <errno.h> 25#include <fcntl.h> 26#include <vector> 27#include <string> 28 29#include <sys/types.h> 30#include <sys/stat.h> 31#include <sys/types.h> 32#include <sys/mman.h> 33#include <sys/mount.h> 34#include <sys/wait.h> 35 36#include <linux/kdev_t.h> 37 38#define LOG_TAG "Vold" 39 40#include <android-base/logging.h> 41#include <android-base/properties.h> 42#include <android-base/stringprintf.h> 43#include <cutils/log.h> 44#include <cutils/properties.h> 45#include <logwrap/logwrap.h> 46#include <selinux/selinux.h> 47 48#include "Ext4.h" 49#include "Ext4Crypt.h" 50#include "Utils.h" 51#include "VoldUtil.h" 52 53using android::base::StringPrintf; 54 55namespace android { 56namespace vold { 57namespace ext4 { 58 59static const char* kResizefsPath = "/system/bin/resize2fs"; 60static const char* kMkfsPath = "/system/bin/mke2fs"; 61static const char* kFsckPath = "/system/bin/e2fsck"; 62 63bool IsSupported() { 64 return access(kMkfsPath, X_OK) == 0 65 && access(kFsckPath, X_OK) == 0 66 && IsFilesystemSupported("ext4"); 67} 68 69status_t Check(const std::string& source, const std::string& target) { 70 // The following is shamelessly borrowed from fs_mgr.c, so it should be 71 // kept in sync with any changes over there. 72 73 const char* c_source = source.c_str(); 74 const char* c_target = target.c_str(); 75 76 int status; 77 int ret; 78 long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID; 79 char *tmpmnt_opts = (char*) "nomblk_io_submit,errors=remount-ro"; 80 81 /* 82 * First try to mount and unmount the filesystem. We do this because 83 * the kernel is more efficient than e2fsck in running the journal and 84 * processing orphaned inodes, and on at least one device with a 85 * performance issue in the emmc firmware, it can take e2fsck 2.5 minutes 86 * to do what the kernel does in about a second. 87 * 88 * After mounting and unmounting the filesystem, run e2fsck, and if an 89 * error is recorded in the filesystem superblock, e2fsck will do a full 90 * check. Otherwise, it does nothing. If the kernel cannot mount the 91 * filesytsem due to an error, e2fsck is still run to do a full check 92 * fix the filesystem. 93 */ 94 ret = mount(c_source, c_target, "ext4", tmpmnt_flags, tmpmnt_opts); 95 if (!ret) { 96 int i; 97 for (i = 0; i < 5; i++) { 98 // Try to umount 5 times before continuing on. 99 // Should we try rebooting if all attempts fail? 100 int result = umount(c_target); 101 if (result == 0) { 102 break; 103 } 104 ALOGW("%s(): umount(%s)=%d: %s\n", __func__, c_target, result, strerror(errno)); 105 sleep(1); 106 } 107 } 108 109 /* 110 * Some system images do not have e2fsck for licensing reasons 111 * (e.g. recent SDK system images). Detect these and skip the check. 112 */ 113 if (access(kFsckPath, X_OK)) { 114 ALOGD("Not running %s on %s (executable not in system image)\n", 115 kFsckPath, c_source); 116 } else { 117 ALOGD("Running %s on %s\n", kFsckPath, c_source); 118 119 std::vector<std::string> cmd; 120 cmd.push_back(kFsckPath); 121 cmd.push_back("-y"); 122 cmd.push_back(c_source); 123 124 // ext4 devices are currently always trusted 125 return ForkExecvp(cmd, sFsckContext); 126 } 127 128 return 0; 129} 130 131status_t Mount(const std::string& source, const std::string& target, bool ro, 132 bool remount, bool executable) { 133 int rc; 134 unsigned long flags; 135 136 const char* c_source = source.c_str(); 137 const char* c_target = target.c_str(); 138 139 flags = MS_NOATIME | MS_NODEV | MS_NOSUID | MS_DIRSYNC; 140 141 flags |= (executable ? 0 : MS_NOEXEC); 142 flags |= (ro ? MS_RDONLY : 0); 143 flags |= (remount ? MS_REMOUNT : 0); 144 145 rc = mount(c_source, c_target, "ext4", flags, NULL); 146 147 if (rc && errno == EROFS) { 148 SLOGE("%s appears to be a read only filesystem - retrying mount RO", c_source); 149 flags |= MS_RDONLY; 150 rc = mount(c_source, c_target, "ext4", flags, NULL); 151 } 152 153 return rc; 154} 155 156status_t Resize(const std::string& source, unsigned long numSectors) { 157 std::vector<std::string> cmd; 158 cmd.push_back(kResizefsPath); 159 cmd.push_back("-f"); 160 cmd.push_back(source); 161 cmd.push_back(StringPrintf("%lu", numSectors)); 162 163 return ForkExecvp(cmd); 164} 165 166status_t Format(const std::string& source, unsigned long numSectors, 167 const std::string& target) { 168 std::vector<std::string> cmd; 169 cmd.push_back(kMkfsPath); 170 171 cmd.push_back("-b"); 172 cmd.push_back("4096"); 173 174 cmd.push_back("-t"); 175 cmd.push_back("ext4"); 176 177 cmd.push_back("-M"); 178 cmd.push_back(target); 179 180 std::string options("has_journal"); 181 if (android::base::GetBoolProperty("vold.has_quota", false)) { 182 options += ",quota"; 183 } 184 if (e4crypt_is_native()) { 185 options += ",encrypt"; 186 } 187 188 cmd.push_back("-O"); 189 cmd.push_back(options); 190 191 cmd.push_back(source); 192 193 if (numSectors) { 194 cmd.push_back(StringPrintf("%lu", numSectors * (4096 / 512))); 195 } 196 197 return ForkExecvp(cmd); 198} 199 200} // namespace ext4 201} // namespace vold 202} // namespace android 203