Re: [PATCH v1 2/5] x86/sev: Move sev_guest.h into common SEV header

[Tom Lendacky <thomas.lendacky@amd.com>]

On 6/21/24 08:40, Michael Roth wrote:
> sev_guest.h currently contains various definitions relating to the
> format of SNP_GUEST_REQUEST commands to SNP firmware. Currently only the
> sev-guest driver makes use of them, but when the KVM side of this is
> implemented there's a need to parse the SNP_GUEST_REQUEST header to
> determine whether additional information needs to be provided to the
> guest. Prepare for this by moving those definitions to a common header
> that's shared by host/guest code so that KVM can also make use of them.
> 
> Signed-off-by: Michael Roth <michael.roth@amd.com>

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>

Nikunj does something similar in his Secure TSC patches. So depending on
which series goes in first...

Thanks,
Tom

> ---
>  arch/x86/include/asm/sev.h              | 48 +++++++++++++++++++
>  drivers/virt/coco/sev-guest/sev-guest.c |  2 -
>  drivers/virt/coco/sev-guest/sev-guest.h | 63 -------------------------
>  3 files changed, 48 insertions(+), 65 deletions(-)
>  delete mode 100644 drivers/virt/coco/sev-guest/sev-guest.h
> 
> diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
> index 1936f37e3371..72f9ba3a2fee 100644
> --- a/arch/x86/include/asm/sev.h
> +++ b/arch/x86/include/asm/sev.h
> @@ -119,6 +119,54 @@ struct snp_req_data {
>  	unsigned int data_npages;
>  };
>  
> +#define MAX_AUTHTAG_LEN		32
> +
> +/* See SNP spec SNP_GUEST_REQUEST section for the structure */
> +enum msg_type {
> +	SNP_MSG_TYPE_INVALID = 0,
> +	SNP_MSG_CPUID_REQ,
> +	SNP_MSG_CPUID_RSP,
> +	SNP_MSG_KEY_REQ,
> +	SNP_MSG_KEY_RSP,
> +	SNP_MSG_REPORT_REQ,
> +	SNP_MSG_REPORT_RSP,
> +	SNP_MSG_EXPORT_REQ,
> +	SNP_MSG_EXPORT_RSP,
> +	SNP_MSG_IMPORT_REQ,
> +	SNP_MSG_IMPORT_RSP,
> +	SNP_MSG_ABSORB_REQ,
> +	SNP_MSG_ABSORB_RSP,
> +	SNP_MSG_VMRK_REQ,
> +	SNP_MSG_VMRK_RSP,
> +
> +	SNP_MSG_TYPE_MAX
> +};
> +
> +enum aead_algo {
> +	SNP_AEAD_INVALID,
> +	SNP_AEAD_AES_256_GCM,
> +};
> +
> +struct snp_guest_msg_hdr {
> +	u8 authtag[MAX_AUTHTAG_LEN];
> +	u64 msg_seqno;
> +	u8 rsvd1[8];
> +	u8 algo;
> +	u8 hdr_version;
> +	u16 hdr_sz;
> +	u8 msg_type;
> +	u8 msg_version;
> +	u16 msg_sz;
> +	u32 rsvd2;
> +	u8 msg_vmpck;
> +	u8 rsvd3[35];
> +} __packed;
> +
> +struct snp_guest_msg {
> +	struct snp_guest_msg_hdr hdr;
> +	u8 payload[4000];
> +} __packed;
> +
>  struct sev_guest_platform_data {
>  	u64 secrets_gpa;
>  };
> diff --git a/drivers/virt/coco/sev-guest/sev-guest.c b/drivers/virt/coco/sev-guest/sev-guest.c
> index 654290a8e1ba..f0ea26f18cbf 100644
> --- a/drivers/virt/coco/sev-guest/sev-guest.c
> +++ b/drivers/virt/coco/sev-guest/sev-guest.c
> @@ -29,8 +29,6 @@
>  #include <asm/svm.h>
>  #include <asm/sev.h>
>  
> -#include "sev-guest.h"
> -
>  #define DEVICE_NAME	"sev-guest"
>  #define AAD_LEN		48
>  #define MSG_HDR_VER	1
> diff --git a/drivers/virt/coco/sev-guest/sev-guest.h b/drivers/virt/coco/sev-guest/sev-guest.h
> deleted file mode 100644
> index 21bda26fdb95..000000000000
> --- a/drivers/virt/coco/sev-guest/sev-guest.h
> +++ /dev/null
> @@ -1,63 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-only */
> -/*
> - * Copyright (C) 2021 Advanced Micro Devices, Inc.
> - *
> - * Author: Brijesh Singh <brijesh.singh@amd.com>
> - *
> - * SEV-SNP API spec is available at https://developer.amd.com/sev
> - */
> -
> -#ifndef __VIRT_SEVGUEST_H__
> -#define __VIRT_SEVGUEST_H__
> -
> -#include <linux/types.h>
> -
> -#define MAX_AUTHTAG_LEN		32
> -
> -/* See SNP spec SNP_GUEST_REQUEST section for the structure */
> -enum msg_type {
> -	SNP_MSG_TYPE_INVALID = 0,
> -	SNP_MSG_CPUID_REQ,
> -	SNP_MSG_CPUID_RSP,
> -	SNP_MSG_KEY_REQ,
> -	SNP_MSG_KEY_RSP,
> -	SNP_MSG_REPORT_REQ,
> -	SNP_MSG_REPORT_RSP,
> -	SNP_MSG_EXPORT_REQ,
> -	SNP_MSG_EXPORT_RSP,
> -	SNP_MSG_IMPORT_REQ,
> -	SNP_MSG_IMPORT_RSP,
> -	SNP_MSG_ABSORB_REQ,
> -	SNP_MSG_ABSORB_RSP,
> -	SNP_MSG_VMRK_REQ,
> -	SNP_MSG_VMRK_RSP,
> -
> -	SNP_MSG_TYPE_MAX
> -};
> -
> -enum aead_algo {
> -	SNP_AEAD_INVALID,
> -	SNP_AEAD_AES_256_GCM,
> -};
> -
> -struct snp_guest_msg_hdr {
> -	u8 authtag[MAX_AUTHTAG_LEN];
> -	u64 msg_seqno;
> -	u8 rsvd1[8];
> -	u8 algo;
> -	u8 hdr_version;
> -	u16 hdr_sz;
> -	u8 msg_type;
> -	u8 msg_version;
> -	u16 msg_sz;
> -	u32 rsvd2;
> -	u8 msg_vmpck;
> -	u8 rsvd3[35];
> -} __packed;
> -
> -struct snp_guest_msg {
> -	struct snp_guest_msg_hdr hdr;
> -	u8 payload[4000];
> -} __packed;
> -
> -#endif /* __VIRT_SEVGUEST_H__ */