| 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
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| 2 | /* |
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| 3 | * Confidential Computing Platform Capability checks |
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| 4 | * |
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| 5 | * Copyright (C) 2021 Advanced Micro Devices, Inc. |
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| 6 | * |
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| 7 | * Author: Tom Lendacky <thomas.lendacky@amd.com> |
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| 8 | */ |
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| 9 | |
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| 10 | #ifndef _LINUX_CC_PLATFORM_H |
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| 11 | #define _LINUX_CC_PLATFORM_H |
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| 12 | |
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| 13 | #include <linux/types.h> |
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| 14 | #include <linux/stddef.h> |
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| 15 | |
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| 16 | /** |
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| 17 | * enum cc_attr - Confidential computing attributes |
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| 18 | * |
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| 19 | * These attributes represent confidential computing features that are |
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| 20 | * currently active. |
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| 21 | */ |
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| 22 | enum cc_attr { |
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| 23 | /** |
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| 24 | * @CC_ATTR_MEM_ENCRYPT: Memory encryption is active |
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| 25 | * |
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| 26 | * The platform/OS is running with active memory encryption. This |
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| 27 | * includes running either as a bare-metal system or a hypervisor |
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| 28 | * and actively using memory encryption or as a guest/virtual machine |
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| 29 | * and actively using memory encryption. |
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| 30 | * |
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| 31 | * Examples include SME, SEV and SEV-ES. |
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| 32 | */ |
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| 33 | CC_ATTR_MEM_ENCRYPT, |
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| 34 | |
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| 35 | /** |
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| 36 | * @CC_ATTR_HOST_MEM_ENCRYPT: Host memory encryption is active |
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| 37 | * |
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| 38 | * The platform/OS is running as a bare-metal system or a hypervisor |
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| 39 | * and actively using memory encryption. |
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| 40 | * |
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| 41 | * Examples include SME. |
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| 42 | */ |
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| 43 | CC_ATTR_HOST_MEM_ENCRYPT, |
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| 44 | |
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| 45 | /** |
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| 46 | * @CC_ATTR_GUEST_MEM_ENCRYPT: Guest memory encryption is active |
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| 47 | * |
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| 48 | * The platform/OS is running as a guest/virtual machine and actively |
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| 49 | * using memory encryption. |
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| 50 | * |
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| 51 | * Examples include SEV and SEV-ES. |
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| 52 | */ |
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| 53 | CC_ATTR_GUEST_MEM_ENCRYPT, |
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| 54 | |
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| 55 | /** |
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| 56 | * @CC_ATTR_GUEST_STATE_ENCRYPT: Guest state encryption is active |
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| 57 | * |
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| 58 | * The platform/OS is running as a guest/virtual machine and actively |
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| 59 | * using memory encryption and register state encryption. |
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| 60 | * |
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| 61 | * Examples include SEV-ES. |
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| 62 | */ |
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| 63 | CC_ATTR_GUEST_STATE_ENCRYPT, |
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| 64 | |
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| 65 | /** |
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| 66 | * @CC_ATTR_GUEST_UNROLL_STRING_IO: String I/O is implemented with |
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| 67 | * IN/OUT instructions |
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| 68 | * |
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| 69 | * The platform/OS is running as a guest/virtual machine and uses |
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| 70 | * IN/OUT instructions in place of string I/O. |
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| 71 | * |
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| 72 | * Examples include TDX guest & SEV. |
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| 73 | */ |
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| 74 | CC_ATTR_GUEST_UNROLL_STRING_IO, |
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| 75 | |
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| 76 | /** |
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| 77 | * @CC_ATTR_SEV_SNP: Guest SNP is active. |
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| 78 | * |
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| 79 | * The platform/OS is running as a guest/virtual machine and actively |
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| 80 | * using AMD SEV-SNP features. |
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| 81 | */ |
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| 82 | CC_ATTR_GUEST_SEV_SNP, |
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| 83 | |
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| 84 | /** |
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| 85 | * @CC_ATTR_GUEST_SNP_SECURE_TSC: SNP Secure TSC is active. |
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| 86 | * |
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| 87 | * The platform/OS is running as a guest/virtual machine and actively |
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| 88 | * using AMD SEV-SNP Secure TSC feature. |
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| 89 | */ |
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| 90 | CC_ATTR_GUEST_SNP_SECURE_TSC, |
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| 91 | |
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| 92 | /** |
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| 93 | * @CC_ATTR_HOST_SEV_SNP: AMD SNP enabled on the host. |
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| 94 | * |
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| 95 | * The host kernel is running with the necessary features |
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| 96 | * enabled to run SEV-SNP guests. |
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| 97 | */ |
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| 98 | CC_ATTR_HOST_SEV_SNP, |
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| 99 | }; |
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| 100 | |
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| 101 | #ifdef CONFIG_ARCH_HAS_CC_PLATFORM |
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| 102 | |
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| 103 | /** |
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| 104 | * cc_platform_has() - Checks if the specified cc_attr attribute is active |
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| 105 | * @attr: Confidential computing attribute to check |
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| 106 | * |
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| 107 | * The cc_platform_has() function will return an indicator as to whether the |
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| 108 | * specified Confidential Computing attribute is currently active. |
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| 109 | * |
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| 110 | * Context: Any context |
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| 111 | * Return: |
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| 112 | * * TRUE - Specified Confidential Computing attribute is active |
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| 113 | * * FALSE - Specified Confidential Computing attribute is not active |
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| 114 | */ |
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| 115 | bool cc_platform_has(enum cc_attr attr); |
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| 116 | void cc_platform_set(enum cc_attr attr); |
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| 117 | void cc_platform_clear(enum cc_attr attr); |
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| 118 | |
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| 119 | #else /* !CONFIG_ARCH_HAS_CC_PLATFORM */ |
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| 120 | |
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| 121 | static inline bool cc_platform_has(enum cc_attr attr) { return false; } |
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| 122 | static inline void cc_platform_set(enum cc_attr attr) { } |
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| 123 | static inline void cc_platform_clear(enum cc_attr attr) { } |
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| 124 | |
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| 125 | #endif /* CONFIG_ARCH_HAS_CC_PLATFORM */ |
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| 126 | |
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| 127 | #endif /* _LINUX_CC_PLATFORM_H */ |
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| 128 | |
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