linux-stable/arch/x86/include/asm/mem_encrypt.h
Sean Christopherson 4daf2a1c45 x86/sev: Drop redundant and potentially misleading 'sev_enabled'
Drop the sev_enabled flag and switch its one user over to sev_active().
sev_enabled was made redundant with the introduction of sev_status in
commit b57de6cd16 ("x86/sev-es: Add SEV-ES Feature Detection").
sev_enabled and sev_active() are guaranteed to be equivalent, as each is
true iff 'sev_status & MSR_AMD64_SEV_ENABLED' is true, and are only ever
written in tandem (ignoring compressed boot's version of sev_status).

Removing sev_enabled avoids confusion over whether it refers to the guest
or the host, and will also allow KVM to usurp "sev_enabled" for its own
purposes.

No functional change intended.

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210422021125.3417167-7-seanjc@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-04-26 05:27:14 -04:00

116 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* AMD Memory Encryption Support
*
* Copyright (C) 2016 Advanced Micro Devices, Inc.
*
* Author: Tom Lendacky <thomas.lendacky@amd.com>
*/
#ifndef __X86_MEM_ENCRYPT_H__
#define __X86_MEM_ENCRYPT_H__
#ifndef __ASSEMBLY__
#include <linux/init.h>
#include <asm/bootparam.h>
#ifdef CONFIG_AMD_MEM_ENCRYPT
extern u64 sme_me_mask;
extern u64 sev_status;
void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr,
unsigned long decrypted_kernel_vaddr,
unsigned long kernel_len,
unsigned long encryption_wa,
unsigned long encryption_pgd);
void __init sme_early_encrypt(resource_size_t paddr,
unsigned long size);
void __init sme_early_decrypt(resource_size_t paddr,
unsigned long size);
void __init sme_map_bootdata(char *real_mode_data);
void __init sme_unmap_bootdata(char *real_mode_data);
void __init sme_early_init(void);
void __init sev_setup_arch(void);
void __init sme_encrypt_kernel(struct boot_params *bp);
void __init sme_enable(struct boot_params *bp);
int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size);
int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
void __init mem_encrypt_free_decrypted_mem(void);
/* Architecture __weak replacement functions */
void __init mem_encrypt_init(void);
void __init sev_es_init_vc_handling(void);
bool sme_active(void);
bool sev_active(void);
bool sev_es_active(void);
#define __bss_decrypted __section(".bss..decrypted")
#else /* !CONFIG_AMD_MEM_ENCRYPT */
#define sme_me_mask 0ULL
static inline void __init sme_early_encrypt(resource_size_t paddr,
unsigned long size) { }
static inline void __init sme_early_decrypt(resource_size_t paddr,
unsigned long size) { }
static inline void __init sme_map_bootdata(char *real_mode_data) { }
static inline void __init sme_unmap_bootdata(char *real_mode_data) { }
static inline void __init sme_early_init(void) { }
static inline void __init sev_setup_arch(void) { }
static inline void __init sme_encrypt_kernel(struct boot_params *bp) { }
static inline void __init sme_enable(struct boot_params *bp) { }
static inline void sev_es_init_vc_handling(void) { }
static inline bool sme_active(void) { return false; }
static inline bool sev_active(void) { return false; }
static inline bool sev_es_active(void) { return false; }
static inline int __init
early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; }
static inline int __init
early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0; }
static inline void mem_encrypt_free_decrypted_mem(void) { }
#define __bss_decrypted
#endif /* CONFIG_AMD_MEM_ENCRYPT */
/*
* The __sme_pa() and __sme_pa_nodebug() macros are meant for use when
* writing to or comparing values from the cr3 register. Having the
* encryption mask set in cr3 enables the PGD entry to be encrypted and
* avoid special case handling of PGD allocations.
*/
#define __sme_pa(x) (__pa(x) | sme_me_mask)
#define __sme_pa_nodebug(x) (__pa_nodebug(x) | sme_me_mask)
extern char __start_bss_decrypted[], __end_bss_decrypted[], __start_bss_decrypted_unused[];
static inline bool mem_encrypt_active(void)
{
return sme_me_mask;
}
static inline u64 sme_get_me_mask(void)
{
return sme_me_mask;
}
#endif /* __ASSEMBLY__ */
#endif /* __X86_MEM_ENCRYPT_H__ */