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 <ext4_utils/ext4_crypt.h> 46 #include <logwrap/logwrap.h> 47 #include <selinux/selinux.h> 48 49 #include "Ext4.h" 50 #include "Ext4Crypt.h" 51 #include "Utils.h" 52 #include "VoldUtil.h" 53 54 using android::base::StringPrintf; 55 56 namespace android { 57 namespace vold { 58 namespace ext4 { 59 60 static const char* kResizefsPath = "/system/bin/resize2fs"; 61 static const char* kMkfsPath = "/system/bin/mke2fs"; 62 static const char* kFsckPath = "/system/bin/e2fsck"; 63 64 bool IsSupported() { 65 return access(kMkfsPath, X_OK) == 0 66 && access(kFsckPath, X_OK) == 0 67 && IsFilesystemSupported("ext4"); 68 } 69 70 status_t Check(const std::string& source, const std::string& target) { 71 // The following is shamelessly borrowed from fs_mgr.c, so it should be 72 // kept in sync with any changes over there. 73 74 const char* c_source = source.c_str(); 75 const char* c_target = target.c_str(); 76 77 int status; 78 int ret; 79 long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID; 80 char *tmpmnt_opts = (char*) "nomblk_io_submit,errors=remount-ro"; 81 82 /* 83 * First try to mount and unmount the filesystem. We do this because 84 * the kernel is more efficient than e2fsck in running the journal and 85 * processing orphaned inodes, and on at least one device with a 86 * performance issue in the emmc firmware, it can take e2fsck 2.5 minutes 87 * to do what the kernel does in about a second. 88 * 89 * After mounting and unmounting the filesystem, run e2fsck, and if an 90 * error is recorded in the filesystem superblock, e2fsck will do a full 91 * check. Otherwise, it does nothing. If the kernel cannot mount the 92 * filesytsem due to an error, e2fsck is still run to do a full check 93 * fix the filesystem. 94 */ 95 ret = mount(c_source, c_target, "ext4", tmpmnt_flags, tmpmnt_opts); 96 if (!ret) { 97 int i; 98 for (i = 0; i < 5; i++) { 99 // Try to umount 5 times before continuing on. 100 // Should we try rebooting if all attempts fail? 101 int result = umount(c_target); 102 if (result == 0) { 103 break; 104 } 105 ALOGW("%s(): umount(%s)=%d: %s\n", __func__, c_target, result, strerror(errno)); 106 sleep(1); 107 } 108 } 109 110 /* 111 * Some system images do not have e2fsck for licensing reasons 112 * (e.g. recent SDK system images). Detect these and skip the check. 113 */ 114 if (access(kFsckPath, X_OK)) { 115 ALOGD("Not running %s on %s (executable not in system image)\n", 116 kFsckPath, c_source); 117 } else { 118 ALOGD("Running %s on %s\n", kFsckPath, c_source); 119 120 std::vector<std::string> cmd; 121 cmd.push_back(kFsckPath); 122 cmd.push_back("-y"); 123 cmd.push_back(c_source); 124 125 // ext4 devices are currently always trusted 126 return ForkExecvp(cmd, sFsckContext); 127 } 128 129 return 0; 130 } 131 132 status_t Mount(const std::string& source, const std::string& target, bool ro, 133 bool remount, bool executable) { 134 int rc; 135 unsigned long flags; 136 137 const char* c_source = source.c_str(); 138 const char* c_target = target.c_str(); 139 140 flags = MS_NOATIME | MS_NODEV | MS_NOSUID | MS_DIRSYNC; 141 142 flags |= (executable ? 0 : MS_NOEXEC); 143 flags |= (ro ? MS_RDONLY : 0); 144 flags |= (remount ? MS_REMOUNT : 0); 145 146 rc = mount(c_source, c_target, "ext4", flags, NULL); 147 148 if (rc && errno == EROFS) { 149 LOG(ERROR) << source << " appears to be a read only filesystem - retrying mount RO"; 150 flags |= MS_RDONLY; 151 rc = mount(c_source, c_target, "ext4", flags, NULL); 152 } 153 154 return rc; 155 } 156 157 status_t Resize(const std::string& source, unsigned long numSectors) { 158 std::vector<std::string> cmd; 159 cmd.push_back(kResizefsPath); 160 cmd.push_back("-f"); 161 cmd.push_back(source); 162 cmd.push_back(StringPrintf("%lu", numSectors)); 163 164 return ForkExecvp(cmd); 165 } 166 167 status_t Format(const std::string& source, unsigned long numSectors, 168 const std::string& target) { 169 std::vector<std::string> cmd; 170 cmd.push_back(kMkfsPath); 171 172 cmd.push_back("-b"); 173 cmd.push_back("4096"); 174 175 cmd.push_back("-t"); 176 cmd.push_back("ext4"); 177 178 cmd.push_back("-M"); 179 cmd.push_back(target); 180 181 std::string options("has_journal"); 182 if (android::base::GetBoolProperty("vold.has_quota", false)) { 183 options += ",quota"; 184 } 185 if (e4crypt_is_native()) { 186 options += ",encrypt"; 187 } 188 189 cmd.push_back("-O"); 190 cmd.push_back(options); 191 192 cmd.push_back(source); 193 194 if (numSectors) { 195 cmd.push_back(StringPrintf("%lu", numSectors * (4096 / 512))); 196 } 197 198 return ForkExecvp(cmd); 199 } 200 201 } // namespace ext4 202 } // namespace vold 203 } // namespace android 204
