// Copyright 2023, 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. //! Utility functions. pub(crate) const SIZE_4KB: usize = 4 << 10; /// Computes the low memory page address of the 4KiB page containing a given address. pub(crate) fn page_address(addr: usize) -> u64 { (addr & !(SIZE_4KB - 1)).try_into().unwrap() }