| // Copyright 2019 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| /// Bytes per page |
| pub const PAGE_SIZE_BYTES: usize = 4096; |
| |
| /// Size of the a VMO block header. |
| pub const HEADER_SIZE_BYTES: usize = 8; |
| |
| /// Index of the root NODE block. |
| pub const ROOT_PARENT_INDEX: u32 = 0; |
| |
| /// Index of the HEADER block. |
| pub const HEADER_INDEX: u32 = 0; |
| |
| /// Magic number for the Header block. "INSP" in UTF-8 little-endian. |
| pub const HEADER_MAGIC_NUMBER: u32 = 0x50534e49; |
| |
| /// Version number for the Header block. |
| pub const HEADER_VERSION_NUMBER: u32 = 0; |
| |
| /// Maximum number order of a block. |
| pub const NUM_ORDERS: usize = 8; |
| |
| /// The shift for order 0. |
| pub const MIN_ORDER_SHIFT: usize = 4; |
| |
| /// The size for order 0. |
| pub const MIN_ORDER_SIZE: usize = 1 << MIN_ORDER_SHIFT; // 16 bytes |
| |
| /// The shift for order NUM_ORDERS-1 (the maximum order) |
| pub const MAX_ORDER_SHIFT: usize = MIN_ORDER_SHIFT + NUM_ORDERS - 1; |
| |
| /// The size for order NUM_ORDERS-1 (the maximum order) |
| pub const MAX_ORDER_SIZE: usize = 1 << MAX_ORDER_SHIFT; |
| |
| /// Name of the root node |
| pub const ROOT_NAME: &str = "root"; |
| |
| /// Default number of bytes for the VMO: 256K |
| pub const DEFAULT_VMO_SIZE_BYTES: usize = 256 * 1024; |
| |
| /// Minimum size for the VMO: 4K |
| pub const MINIMUM_VMO_SIZE_BYTES: usize = 4 * 1024; |
