projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 51ae4a2d PA |
1 | /* |
| 2 | * Supervisor Mode Access Prevention support | |
| 3 | * | |
| 4 | * Copyright (C) 2012 Intel Corporation | |
| 5 | * Author: H. Peter Anvin <hpa@linux.intel.com> | |
| 6 | * | |
| 7 | * This program is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU General Public License | |
| 9 | * as published by the Free Software Foundation; version 2 | |
| 10 | * of the License. | |
| 11 | */ | |
| 12 | ||
| 13 | #ifndef _ASM_X86_SMAP_H | |
| 14 | #define _ASM_X86_SMAP_H | |
| 15 | ||
| 16 | #include <linux/stringify.h> | |
| 17 | #include <asm/nops.h> | |
| cd4d09ec | 18 | #include <asm/cpufeatures.h> |
| 51ae4a2d PA |
19 | |
| 20 | /* "Raw" instruction opcodes */ | |
| 21 | #define __ASM_CLAC .byte 0x0f,0x01,0xca | |
| 22 | #define __ASM_STAC .byte 0x0f,0x01,0xcb | |
| 23 | ||
| 24 | #ifdef __ASSEMBLY__ | |
| 25 | ||
| 26 | #include <asm/alternative-asm.h> | |
| 27 | ||
| 28 | #ifdef CONFIG_X86_SMAP | |
| 29 | ||
| 669f8a90 BP |
30 | #define ASM_CLAC \ |
| 31 | ALTERNATIVE "", __stringify(__ASM_CLAC), X86_FEATURE_SMAP | |
| 32 | ||
| 33 | #define ASM_STAC \ | |
| 34 | ALTERNATIVE "", __stringify(__ASM_STAC), X86_FEATURE_SMAP | |
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35 | |
| 36 | #else /* CONFIG_X86_SMAP */ | |
| 37 | ||
| 38 | #define ASM_CLAC | |
| 39 | #define ASM_STAC | |
| 40 | ||
| 41 | #endif /* CONFIG_X86_SMAP */ | |
| 42 | ||
| 43 | #else /* __ASSEMBLY__ */ | |
| 44 | ||
| 45 | #include <asm/alternative.h> | |
| 46 | ||
| 47 | #ifdef CONFIG_X86_SMAP | |
| 48 | ||
| 63bcff2a | 49 | static __always_inline void clac(void) |
| 51ae4a2d PA |
50 | { |
| 51 | /* Note: a barrier is implicit in alternative() */ | |
| 669f8a90 | 52 | alternative("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP); |
| 51ae4a2d PA |
53 | } |
| 54 | ||
| 63bcff2a | 55 | static __always_inline void stac(void) |
| 51ae4a2d PA |
56 | { |
| 57 | /* Note: a barrier is implicit in alternative() */ | |
| 669f8a90 | 58 | alternative("", __stringify(__ASM_STAC), X86_FEATURE_SMAP); |
| 51ae4a2d PA |
59 | } |
| 60 | ||
| 61 | /* These macros can be used in asm() statements */ | |
| 62 | #define ASM_CLAC \ | |
| 669f8a90 | 63 | ALTERNATIVE("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP) |
| 51ae4a2d | 64 | #define ASM_STAC \ |
| 669f8a90 | 65 | ALTERNATIVE("", __stringify(__ASM_STAC), X86_FEATURE_SMAP) |
| 51ae4a2d PA |
66 | |
| 67 | #else /* CONFIG_X86_SMAP */ | |
| 68 | ||
| 69 | static inline void clac(void) { } | |
| 70 | static inline void stac(void) { } | |
| 71 | ||
| 72 | #define ASM_CLAC | |
| 73 | #define ASM_STAC | |
| 74 | ||
| 75 | #endif /* CONFIG_X86_SMAP */ | |
| 76 | ||
| 77 | #endif /* __ASSEMBLY__ */ | |
| 78 | ||
| 79 | #endif /* _ASM_X86_SMAP_H */ |