1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Confidential Computing Platform Capability checks 4 * 5 * Copyright (C) 2021 Advanced Micro Devices, Inc. 6 * 7 * Author: Tom Lendacky <[email protected]> 8 */ 9 10 #ifndef _LINUX_CC_PLATFORM_H 11 #define _LINUX_CC_PLATFORM_H 12 13 #include <linux/types.h> 14 #include <linux/stddef.h> 15 16 /** 17 * enum cc_attr - Confidential computing attributes 18 * 19 * These attributes represent confidential computing features that are 20 * currently active. 21 */ 22 enum cc_attr { 23 /** 24 * @CC_ATTR_MEM_ENCRYPT: Memory encryption is active 25 * 26 * The platform/OS is running with active memory encryption. This 27 * includes running either as a bare-metal system or a hypervisor 28 * and actively using memory encryption or as a guest/virtual machine 29 * and actively using memory encryption. 30 * 31 * Examples include SME, SEV and SEV-ES. 32 */ 33 CC_ATTR_MEM_ENCRYPT, 34 35 /** 36 * @CC_ATTR_HOST_MEM_ENCRYPT: Host memory encryption is active 37 * 38 * The platform/OS is running as a bare-metal system or a hypervisor 39 * and actively using memory encryption. 40 * 41 * Examples include SME. 42 */ 43 CC_ATTR_HOST_MEM_ENCRYPT, 44 45 /** 46 * @CC_ATTR_GUEST_MEM_ENCRYPT: Guest memory encryption is active 47 * 48 * The platform/OS is running as a guest/virtual machine and actively 49 * using memory encryption. 50 * 51 * Examples include SEV and SEV-ES. 52 */ 53 CC_ATTR_GUEST_MEM_ENCRYPT, 54 55 /** 56 * @CC_ATTR_GUEST_STATE_ENCRYPT: Guest state encryption is active 57 * 58 * The platform/OS is running as a guest/virtual machine and actively 59 * using memory encryption and register state encryption. 60 * 61 * Examples include SEV-ES. 62 */ 63 CC_ATTR_GUEST_STATE_ENCRYPT, 64 }; 65 66 #ifdef CONFIG_ARCH_HAS_CC_PLATFORM 67 68 /** 69 * cc_platform_has() - Checks if the specified cc_attr attribute is active 70 * @attr: Confidential computing attribute to check 71 * 72 * The cc_platform_has() function will return an indicator as to whether the 73 * specified Confidential Computing attribute is currently active. 74 * 75 * Context: Any context 76 * Return: 77 * * TRUE - Specified Confidential Computing attribute is active 78 * * FALSE - Specified Confidential Computing attribute is not active 79 */ 80 bool cc_platform_has(enum cc_attr attr); 81 82 #else /* !CONFIG_ARCH_HAS_CC_PLATFORM */ 83 84 static inline bool cc_platform_has(enum cc_attr attr) { return false; } 85 86 #endif /* CONFIG_ARCH_HAS_CC_PLATFORM */ 87 88 #endif /* _LINUX_CC_PLATFORM_H */ 89