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_recovery.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 26 #include "update_engine/common/utils.h" 27 #include "update_engine/utils_android.h" 28 29 using std::string; 30 31 #ifndef _UE_SIDELOAD 32 #error "BootControlRecovery should only be used for update_engine_sideload." 33 #endif 34 35 // When called from update_engine_sideload, we don't attempt to dynamically load 36 // the right boot_control HAL, instead we use the only HAL statically linked in 37 // via the PRODUCT_STATIC_BOOT_CONTROL_HAL make variable and access the module 38 // struct directly. 39 extern const hw_module_t HAL_MODULE_INFO_SYM; 40 41 namespace chromeos_update_engine { 42 43 namespace boot_control { 44 45 // Factory defined in boot_control.h. 46 std::unique_ptr<BootControlInterface> CreateBootControl() { 47 std::unique_ptr<BootControlRecovery> boot_control(new BootControlRecovery()); 48 if (!boot_control->Init()) { 49 return nullptr; 50 } 51 return std::move(boot_control); 52 } 53 54 } // namespace boot_control 55 56 bool BootControlRecovery::Init() { 57 const hw_module_t* hw_module; 58 int ret; 59 60 // For update_engine_sideload, we simulate the hw_get_module() by accessing it 61 // from the current process directly. 62 hw_module = &HAL_MODULE_INFO_SYM; 63 ret = 0; 64 if (!hw_module || 65 strcmp(BOOT_CONTROL_HARDWARE_MODULE_ID, hw_module->id) != 0) { 66 ret = -EINVAL; 67 } 68 if (ret != 0) { 69 LOG(ERROR) << "Error loading boot_control HAL implementation."; 70 return false; 71 } 72 73 module_ = reinterpret_cast<boot_control_module_t*>( 74 const_cast<hw_module_t*>(hw_module)); 75 module_->init(module_); 76 77 LOG(INFO) << "Loaded boot_control HAL " 78 << "'" << hw_module->name << "' " 79 << "version " << (hw_module->module_api_version >> 8) << "." 80 << (hw_module->module_api_version & 0xff) << " " 81 << "authored by '" << hw_module->author << "'."; 82 return true; 83 } 84 85 unsigned int BootControlRecovery::GetNumSlots() const { 86 return module_->getNumberSlots(module_); 87 } 88 89 BootControlInterface::Slot BootControlRecovery::GetCurrentSlot() const { 90 return module_->getCurrentSlot(module_); 91 } 92 93 bool BootControlRecovery::GetPartitionDevice(const string& partition_name, 94 Slot slot, 95 string* device) const { 96 // We can't use fs_mgr to look up |partition_name| because fstab 97 // doesn't list every slot partition (it uses the slotselect option 98 // to mask the suffix). 99 // 100 // We can however assume that there's an entry for the /misc mount 101 // point and use that to get the device file for the misc 102 // partition. This helps us locate the disk that |partition_name| 103 // resides on. From there we'll assume that a by-name scheme is used 104 // so we can just replace the trailing "misc" by the given 105 // |partition_name| and suffix corresponding to |slot|, e.g. 106 // 107 // /dev/block/platform/soc.0/7824900.sdhci/by-name/misc -> 108 // /dev/block/platform/soc.0/7824900.sdhci/by-name/boot_a 109 // 110 // If needed, it's possible to relax the by-name assumption in the 111 // future by trawling /sys/block looking for the appropriate sibling 112 // of misc and then finding an entry in /dev matching the sysfs 113 // entry. 114 115 base::FilePath misc_device; 116 if (!utils::DeviceForMountPoint("/misc", &misc_device)) 117 return false; 118 119 if (!utils::IsSymlink(misc_device.value().c_str())) { 120 LOG(ERROR) << "Device file " << misc_device.value() << " for /misc " 121 << "is not a symlink."; 122 return false; 123 } 124 125 const char* suffix = module_->getSuffix(module_, slot); 126 if (suffix == nullptr) { 127 LOG(ERROR) << "boot_control impl returned no suffix for slot " 128 << SlotName(slot); 129 return false; 130 } 131 132 base::FilePath path = misc_device.DirName().Append(partition_name + suffix); 133 if (!base::PathExists(path)) { 134 LOG(ERROR) << "Device file " << path.value() << " does not exist."; 135 return false; 136 } 137 138 *device = path.value(); 139 return true; 140 } 141 142 bool BootControlRecovery::IsSlotBootable(Slot slot) const { 143 int ret = module_->isSlotBootable(module_, slot); 144 if (ret < 0) { 145 LOG(ERROR) << "Unable to determine if slot " << SlotName(slot) 146 << " is bootable: " << strerror(-ret); 147 return false; 148 } 149 return ret == 1; 150 } 151 152 bool BootControlRecovery::MarkSlotUnbootable(Slot slot) { 153 int ret = module_->setSlotAsUnbootable(module_, slot); 154 if (ret < 0) { 155 LOG(ERROR) << "Unable to mark slot " << SlotName(slot) 156 << " as bootable: " << strerror(-ret); 157 return false; 158 } 159 return ret == 0; 160 } 161 162 bool BootControlRecovery::SetActiveBootSlot(Slot slot) { 163 int ret = module_->setActiveBootSlot(module_, slot); 164 if (ret < 0) { 165 LOG(ERROR) << "Unable to set the active slot to slot " << SlotName(slot) 166 << ": " << strerror(-ret); 167 } 168 return ret == 0; 169 } 170 171 bool BootControlRecovery::MarkBootSuccessfulAsync( 172 base::Callback<void(bool)> callback) { 173 int ret = module_->markBootSuccessful(module_); 174 if (ret < 0) { 175 LOG(ERROR) << "Unable to mark boot successful: " << strerror(-ret); 176 } 177 return brillo::MessageLoop::current()->PostTask( 178 FROM_HERE, base::Bind(callback, ret == 0)) != 179 brillo::MessageLoop::kTaskIdNull; 180 } 181 182 } // namespace chromeos_update_engine 183
