1 // 2 // Copyright (C) 2015 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 "update_engine/boot_control_android.h" 18 19 #include <base/bind.h> 20 #include <base/files/file_util.h> 21 #include <base/logging.h> 22 #include <base/strings/string_util.h> 23 #include <brillo/make_unique_ptr.h> 24 #include <brillo/message_loops/message_loop.h> 25 #include <cutils/properties.h> 26 #include <fs_mgr.h> 27 28 #include "update_engine/common/utils.h" 29 30 using std::string; 31 32 namespace { 33 34 // Open the appropriate fstab file and fallback to /fstab.device if 35 // that's what's being used. 36 static struct fstab* OpenFSTab() { 37 char propbuf[PROPERTY_VALUE_MAX]; 38 struct fstab* fstab; 39 40 property_get("ro.hardware", propbuf, ""); 41 string fstab_name = string("/fstab.") + propbuf; 42 fstab = fs_mgr_read_fstab(fstab_name.c_str()); 43 if (fstab != nullptr) 44 return fstab; 45 46 fstab = fs_mgr_read_fstab("/fstab.device"); 47 return fstab; 48 } 49 50 } // namespace 51 52 53 namespace chromeos_update_engine { 54 55 namespace boot_control { 56 57 // Factory defined in boot_control.h. 58 std::unique_ptr<BootControlInterface> CreateBootControl() { 59 std::unique_ptr<BootControlAndroid> boot_control(new BootControlAndroid()); 60 if (!boot_control->Init()) { 61 return nullptr; 62 } 63 return brillo::make_unique_ptr(boot_control.release()); 64 } 65 66 } // namespace boot_control 67 68 bool BootControlAndroid::Init() { 69 const hw_module_t* hw_module; 70 int ret; 71 72 ret = hw_get_module(BOOT_CONTROL_HARDWARE_MODULE_ID, &hw_module); 73 if (ret != 0) { 74 LOG(ERROR) << "Error loading boot_control HAL implementation."; 75 return false; 76 } 77 78 module_ = reinterpret_cast<boot_control_module_t*>(const_cast<hw_module_t*>(hw_module)); 79 module_->init(module_); 80 81 LOG(INFO) << "Loaded boot_control HAL " 82 << "'" << hw_module->name << "' " 83 << "version " << (hw_module->module_api_version>>8) << "." 84 << (hw_module->module_api_version&0xff) << " " 85 << "authored by '" << hw_module->author << "'."; 86 return true; 87 } 88 89 unsigned int BootControlAndroid::GetNumSlots() const { 90 return module_->getNumberSlots(module_); 91 } 92 93 BootControlInterface::Slot BootControlAndroid::GetCurrentSlot() const { 94 return module_->getCurrentSlot(module_); 95 } 96 97 bool BootControlAndroid::GetPartitionDevice(const string& partition_name, 98 Slot slot, 99 string* device) const { 100 struct fstab* fstab; 101 struct fstab_rec* record; 102 103 // We can't use fs_mgr to look up |partition_name| because fstab 104 // doesn't list every slot partition (it uses the slotselect option 105 // to mask the suffix). 106 // 107 // We can however assume that there's an entry for the /misc mount 108 // point and use that to get the device file for the misc 109 // partition. This helps us locate the disk that |partition_name| 110 // resides on. From there we'll assume that a by-name scheme is used 111 // so we can just replace the trailing "misc" by the given 112 // |partition_name| and suffix corresponding to |slot|, e.g. 113 // 114 // /dev/block/platform/soc.0/7824900.sdhci/by-name/misc -> 115 // /dev/block/platform/soc.0/7824900.sdhci/by-name/boot_a 116 // 117 // If needed, it's possible to relax the by-name assumption in the 118 // future by trawling /sys/block looking for the appropriate sibling 119 // of misc and then finding an entry in /dev matching the sysfs 120 // entry. 121 122 fstab = OpenFSTab(); 123 if (fstab == nullptr) { 124 LOG(ERROR) << "Error opening fstab file."; 125 return false; 126 } 127 record = fs_mgr_get_entry_for_mount_point(fstab, "/misc"); 128 if (record == nullptr) { 129 LOG(ERROR) << "Error finding /misc entry in fstab file."; 130 fs_mgr_free_fstab(fstab); 131 return false; 132 } 133 134 base::FilePath misc_device = base::FilePath(record->blk_device); 135 fs_mgr_free_fstab(fstab); 136 137 if (!utils::IsSymlink(misc_device.value().c_str())) { 138 LOG(ERROR) << "Device file " << misc_device.value() << " for /misc " 139 << "is not a symlink."; 140 return false; 141 } 142 143 const char* suffix = module_->getSuffix(module_, slot); 144 if (suffix == nullptr) { 145 LOG(ERROR) << "boot_control impl returned no suffix for slot " 146 << SlotName(slot); 147 return false; 148 } 149 150 base::FilePath path = misc_device.DirName().Append(partition_name + suffix); 151 if (!base::PathExists(path)) { 152 LOG(ERROR) << "Device file " << path.value() << " does not exist."; 153 return false; 154 } 155 156 *device = path.value(); 157 return true; 158 } 159 160 bool BootControlAndroid::IsSlotBootable(Slot slot) const { 161 int ret = module_->isSlotBootable(module_, slot); 162 if (ret < 0) { 163 LOG(ERROR) << "Unable to determine if slot " << SlotName(slot) 164 << " is bootable: " << strerror(-ret); 165 return false; 166 } 167 return ret == 1; 168 } 169 170 bool BootControlAndroid::MarkSlotUnbootable(Slot slot) { 171 int ret = module_->setSlotAsUnbootable(module_, slot); 172 if (ret < 0) { 173 LOG(ERROR) << "Unable to mark slot " << SlotName(slot) 174 << " as bootable: " << strerror(-ret); 175 return false; 176 } 177 return ret == 0; 178 } 179 180 bool BootControlAndroid::SetActiveBootSlot(Slot slot) { 181 int ret = module_->setActiveBootSlot(module_, slot); 182 if (ret < 0) { 183 LOG(ERROR) << "Unable to set the active slot to slot " << SlotName(slot) 184 << ": " << strerror(-ret); 185 } 186 return ret == 0; 187 } 188 189 bool BootControlAndroid::MarkBootSuccessfulAsync( 190 base::Callback<void(bool)> callback) { 191 int ret = module_->markBootSuccessful(module_); 192 if (ret < 0) { 193 LOG(ERROR) << "Unable to mark boot successful: " << strerror(-ret); 194 } 195 return brillo::MessageLoop::current()->PostTask( 196 FROM_HERE, base::Bind(callback, ret == 0)) != 197 brillo::MessageLoop::kTaskIdNull; 198 } 199 200 } // namespace chromeos_update_engine 201
