projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 2d21ac55 | 1 | /* |
| 3e170ce0 | 2 | * Copyright (c) 2014 Apple Inc. All rights reserved. |
| 2d21ac55 A |
3 | * |
| 4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ | |
| 0a7de745 | 5 | * |
| 2d21ac55 A |
6 | * This file contains Original Code and/or Modifications of Original Code |
| 7 | * as defined in and that are subject to the Apple Public Source License | |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in | |
| 9 | * compliance with the License. The rights granted to you under the License | |
| 10 | * may not be used to create, or enable the creation or redistribution of, | |
| 11 | * unlawful or unlicensed copies of an Apple operating system, or to | |
| 12 | * circumvent, violate, or enable the circumvention or violation of, any | |
| 13 | * terms of an Apple operating system software license agreement. | |
| 0a7de745 | 14 | * |
| 2d21ac55 A |
15 | * Please obtain a copy of the License at |
| 16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. | |
| 0a7de745 | 17 | * |
| 2d21ac55 A |
18 | * The Original Code and all software distributed under the License are |
| 19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 23 | * Please see the License for the specific language governing rights and | |
| 24 | * limitations under the License. | |
| 0a7de745 | 25 | * |
| 2d21ac55 A |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
| 27 | */ | |
| 28 | ||
| 3e170ce0 A |
29 | #include <mach/vm_param.h> |
| 30 | ||
| 2d21ac55 | 31 | /* |
| 3e170ce0 A |
32 | * This file is compiled and linked to be the last .o of the __const section |
| 33 | * of the __DATA segment (see MakeInc.kernel, lastkernelconstructor is placed | |
| 34 | * in the __LAST segment.) | |
| 35 | * | |
| 36 | * This blank page allows us to safely map the const section RO while the rest | |
| 37 | * of __DATA is RW. This is needed since ld has no way of specifying section size | |
| 38 | * alignment and no straight forward way to specify section ordering. | |
| 2d21ac55 A |
39 | */ |
| 40 | ||
| 5ba3f43e A |
41 | #if defined(__arm64__) |
| 42 | /* PAGE_SIZE on ARM64 is an expression derived from a non-const global variable */ | |
| 0a7de745 | 43 | #define PAD_SIZE PAGE_MAX_SIZE |
| 5ba3f43e | 44 | #else |
| 0a7de745 | 45 | #define PAD_SIZE PAGE_SIZE |
| 5ba3f43e | 46 | #endif |
| 2d21ac55 | 47 | |
| 0a7de745 | 48 | static const uint8_t __attribute__((section("__DATA,__const"))) data_const_padding[PAD_SIZE] = {[0 ... PAD_SIZE - 1] = 0xFF}; |
| 3e170ce0 A |
49 | const vm_offset_t __attribute__((section("__DATA,__data"))) _lastkerneldataconst = (vm_offset_t)&data_const_padding[0]; |
| 50 | const vm_size_t __attribute__((section("__DATA,__data"))) _lastkerneldataconst_padsize = sizeof(data_const_padding); |