aosp12/system/update_engine/common/boot_control_interface.h

128 lines
5.1 KiB
C++

//
// Copyright (C) 2015 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef UPDATE_ENGINE_COMMON_BOOT_CONTROL_INTERFACE_H_
#define UPDATE_ENGINE_COMMON_BOOT_CONTROL_INTERFACE_H_
#include <climits>
#include <map>
#include <string>
#include <vector>
#include <base/callback.h>
#include <base/macros.h>
#include "update_engine/common/dynamic_partition_control_interface.h"
#include "update_engine/update_metadata.pb.h"
namespace chromeos_update_engine {
// The abstract boot control interface defines the interaction with the
// platform's bootloader hiding vendor-specific details from the rest of
// update_engine. This interface is used for controlling where the device should
// boot from.
class BootControlInterface {
public:
using Slot = unsigned int;
static const Slot kInvalidSlot = UINT_MAX;
virtual ~BootControlInterface() = default;
// Return the number of update slots in the system. A system will normally
// have two slots, named "A" and "B" in the documentation, but sometimes
// images running from other media can have only one slot, like some USB
// image. Systems with only one slot won't be able to update.
virtual unsigned int GetNumSlots() const = 0;
// Return the slot where we are running the system from. On success, the
// result is a number between 0 and GetNumSlots() - 1. Otherwise, log an error
// and return kInvalidSlot.
virtual Slot GetCurrentSlot() const = 0;
// Determines the block device for the given partition name and slot number.
// The |slot| number must be between 0 and GetNumSlots() - 1 and the
// |partition_name| is a platform-specific name that identifies a partition on
// every slot. In order to access the dynamic partitions in the target slot,
// GetDynamicPartitionControl()->PreparePartitionsForUpdate() must be called
// (with |update| == true for the first time for a payload, and |false| for
// for the rest of the times) prior to calling this function.
// The handling may be different based on whether the partition is included
// in the update payload. On success, returns true; and stores the block
// device in |device|, if the partition is dynamic in |is_dynamic|.
virtual bool GetPartitionDevice(const std::string& partition_name,
Slot slot,
bool not_in_payload,
std::string* device,
bool* is_dynamic) const = 0;
// Overload of the above function. We assume the partition is always included
// in the payload.
virtual bool GetPartitionDevice(const std::string& partition_name,
Slot slot,
std::string* device) const = 0;
virtual std::optional<PartitionDevice> GetPartitionDevice(
const std::string& partition_name,
uint32_t slot,
uint32_t current_slot,
bool not_in_payload = false) const = 0;
// Returns whether the passed |slot| is marked as bootable. Returns false if
// the slot is invalid.
virtual bool IsSlotBootable(Slot slot) const = 0;
// Mark the specified slot unbootable. No other slot flags are modified.
// Returns true on success.
virtual bool MarkSlotUnbootable(Slot slot) = 0;
// Set the passed |slot| as the preferred boot slot. Returns whether it
// succeeded setting the active slot. If succeeded, on next boot the
// bootloader will attempt to load the |slot| marked as active. Note that this
// method doesn't change the value of GetCurrentSlot() on the current boot.
virtual bool SetActiveBootSlot(Slot slot) = 0;
// Mark the current slot as successfully booted asynchronously. No other slot
// flags are modified. Returns false if it was not able to schedule the
// operation, otherwise, returns true and calls the |callback| with the result
// of the operation.
virtual bool MarkBootSuccessfulAsync(base::Callback<void(bool)> callback) = 0;
// Check if |slot| is marked boot successfully.
virtual bool IsSlotMarkedSuccessful(Slot slot) const = 0;
// Return the dynamic partition control interface. Never null.
virtual DynamicPartitionControlInterface* GetDynamicPartitionControl() = 0;
// Return a human-readable slot name used for logging.
static std::string SlotName(Slot slot) {
if (slot == kInvalidSlot)
return "INVALID";
if (slot < 26)
return std::string(1, 'A' + slot);
return "TOO_BIG";
}
protected:
BootControlInterface() = default;
private:
DISALLOW_COPY_AND_ASSIGN(BootControlInterface);
};
} // namespace chromeos_update_engine
#endif // UPDATE_ENGINE_COMMON_BOOT_CONTROL_INTERFACE_H_