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 #ifndef UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 18 #define UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 19 20 #include <memory> 21 #include <string> 22 23 #include <base/callback.h> 24 #include <gtest/gtest_prod.h> // for FRIEND_TEST 25 26 #include "update_engine/common/boot_control_interface.h" 27 #include "update_engine/common/dynamic_partition_control_interface.h" 28 29 namespace chromeos_update_engine { 30 31 // The Chrome OS implementation of the BootControlInterface. This interface 32 // assumes the partition names and numbers used in Chrome OS devices. 33 class BootControlChromeOS : public BootControlInterface { 34 public: 35 BootControlChromeOS() = default; 36 ~BootControlChromeOS() = default; 37 38 // Initialize the BootControl instance loading the constant values. Returns 39 // whether the operation succeeded. In case of failure, normally meaning 40 // some critical failure such as we couldn't determine the slot that we 41 // booted from, the implementation will pretend that there's only one slot and 42 // therefore A/B updates are disabled. 43 bool Init(); 44 45 // BootControlInterface overrides. 46 unsigned int GetNumSlots() const override; 47 BootControlInterface::Slot GetCurrentSlot() const override; 48 bool GetPartitionDevice(const std::string& partition_name, 49 BootControlInterface::Slot slot, 50 std::string* device) const override; 51 bool IsSlotBootable(BootControlInterface::Slot slot) const override; 52 bool MarkSlotUnbootable(BootControlInterface::Slot slot) override; 53 bool SetActiveBootSlot(BootControlInterface::Slot slot) override; 54 bool MarkBootSuccessfulAsync(base::Callback<void(bool)> callback) override; 55 bool IsSlotMarkedSuccessful(BootControlInterface::Slot slot) const override; 56 DynamicPartitionControlInterface* GetDynamicPartitionControl() override; 57 58 private: 59 friend class BootControlChromeOSTest; 60 FRIEND_TEST(BootControlChromeOSTest, SysfsBlockDeviceTest); 61 FRIEND_TEST(BootControlChromeOSTest, GetPartitionNumberTest); 62 63 // Returns the sysfs block device for a root block device. For example, 64 // SysfsBlockDevice("/dev/sda") returns "/sys/block/sda". Returns an empty 65 // string if the input device is not of the "/dev/xyz" form. 66 static std::string SysfsBlockDevice(const std::string& device); 67 68 // Returns true if the root |device| (e.g., "/dev/sdb") is known to be 69 // removable, false otherwise. 70 static bool IsRemovableDevice(const std::string& device); 71 72 // Return the hard-coded partition number used in Chrome OS for the passed 73 // |partition_name| and |slot|. In case of invalid data, returns -1. 74 int GetPartitionNumber(const std::string partition_name, 75 BootControlInterface::Slot slot) const; 76 77 // Cached values for GetNumSlots() and GetCurrentSlot(). 78 BootControlInterface::Slot num_slots_{1}; 79 BootControlInterface::Slot current_slot_{BootControlInterface::kInvalidSlot}; 80 81 // The block device of the disk we booted from, without the partition number. 82 std::string boot_disk_name_; 83 84 std::unique_ptr<DynamicPartitionControlInterface> dynamic_partition_control_; 85 86 DISALLOW_COPY_AND_ASSIGN(BootControlChromeOS); 87 }; 88 89 } // namespace chromeos_update_engine 90 91 #endif // UPDATE_ENGINE_BOOT_CONTROL_CHROMEOS_H_ 92