| // 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() |
| } |