linux/arch/x86/include/asm/tdx.h
Paolo Bonzini fd02aa45bd Merge branch 'kvm-tdx-initial' into HEAD
This large commit contains the initial support for TDX in KVM.  All x86
parts enable the host-side hypercalls that KVM uses to talk to the TDX
module, a software component that runs in a special CPU mode called SEAM
(Secure Arbitration Mode).

The series is in turn split into multiple sub-series, each with a separate
merge commit:

- Initialization: basic setup for using the TDX module from KVM, plus
  ioctls to create TDX VMs and vCPUs.

- MMU: in TDX, private and shared halves of the address space are mapped by
  different EPT roots, and the private half is managed by the TDX module.
  Using the support that was added to the generic MMU code in 6.14,
  add support for TDX's secure page tables to the Intel side of KVM.
  Generic KVM code takes care of maintaining a mirror of the secure page
  tables so that they can be queried efficiently, and ensuring that changes
  are applied to both the mirror and the secure EPT.

- vCPU enter/exit: implement the callbacks that handle the entry of a TDX
  vCPU (via the SEAMCALL TDH.VP.ENTER) and the corresponding save/restore
  of host state.

- Userspace exits: introduce support for guest TDVMCALLs that KVM forwards to
  userspace.  These correspond to the usual KVM_EXIT_* "heavyweight vmexits"
  but are triggered through a different mechanism, similar to VMGEXIT for
  SEV-ES and SEV-SNP.

- Interrupt handling: support for virtual interrupt injection as well as
  handling VM-Exits that are caused by vectored events.  Exclusive to
  TDX are machine-check SMIs, which the kernel already knows how to
  handle through the kernel machine check handler (commit 7911f145de,
  "x86/mce: Implement recovery for errors in TDX/SEAM non-root mode")

- Loose ends: handling of the remaining exits from the TDX module, including
  EPT violation/misconfig and several TDVMCALL leaves that are handled in
  the kernel (CPUID, HLT, RDMSR/WRMSR, GetTdVmCallInfo); plus returning
  an error or ignoring operations that are not supported by TDX guests

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2025-04-07 07:36:33 -04:00

205 lines
6.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2021-2022 Intel Corporation */
#ifndef _ASM_X86_TDX_H
#define _ASM_X86_TDX_H
#include <linux/init.h>
#include <linux/bits.h>
#include <linux/mmzone.h>
#include <asm/errno.h>
#include <asm/ptrace.h>
#include <asm/trapnr.h>
#include <asm/shared/tdx.h>
/*
* SW-defined error codes.
*
* Bits 47:40 == 0xFF indicate Reserved status code class that never used by
* TDX module.
*/
#define TDX_ERROR _BITUL(63)
#define TDX_NON_RECOVERABLE _BITUL(62)
#define TDX_SW_ERROR (TDX_ERROR | GENMASK_ULL(47, 40))
#define TDX_SEAMCALL_VMFAILINVALID (TDX_SW_ERROR | _UL(0xFFFF0000))
#define TDX_SEAMCALL_GP (TDX_SW_ERROR | X86_TRAP_GP)
#define TDX_SEAMCALL_UD (TDX_SW_ERROR | X86_TRAP_UD)
/*
* TDX module SEAMCALL leaf function error codes
*/
#define TDX_SUCCESS 0ULL
#define TDX_RND_NO_ENTROPY 0x8000020300000000ULL
#ifndef __ASSEMBLER__
#include <uapi/asm/mce.h>
#include <asm/tdx_global_metadata.h>
#include <linux/pgtable.h>
/*
* Used by the #VE exception handler to gather the #VE exception
* info from the TDX module. This is a software only structure
* and not part of the TDX module/VMM ABI.
*/
struct ve_info {
u64 exit_reason;
u64 exit_qual;
/* Guest Linear (virtual) Address */
u64 gla;
/* Guest Physical Address */
u64 gpa;
u32 instr_len;
u32 instr_info;
};
#ifdef CONFIG_INTEL_TDX_GUEST
void __init tdx_early_init(void);
void tdx_get_ve_info(struct ve_info *ve);
bool tdx_handle_virt_exception(struct pt_regs *regs, struct ve_info *ve);
void tdx_halt(void);
bool tdx_early_handle_ve(struct pt_regs *regs);
int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport);
u64 tdx_hcall_get_quote(u8 *buf, size_t size);
void __init tdx_dump_attributes(u64 td_attr);
void __init tdx_dump_td_ctls(u64 td_ctls);
#else
static inline void tdx_early_init(void) { };
static inline void tdx_halt(void) { };
static inline bool tdx_early_handle_ve(struct pt_regs *regs) { return false; }
#endif /* CONFIG_INTEL_TDX_GUEST */
#if defined(CONFIG_KVM_GUEST) && defined(CONFIG_INTEL_TDX_GUEST)
long tdx_kvm_hypercall(unsigned int nr, unsigned long p1, unsigned long p2,
unsigned long p3, unsigned long p4);
#else
static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
unsigned long p2, unsigned long p3,
unsigned long p4)
{
return -ENODEV;
}
#endif /* CONFIG_INTEL_TDX_GUEST && CONFIG_KVM_GUEST */
#ifdef CONFIG_INTEL_TDX_HOST
u64 __seamcall(u64 fn, struct tdx_module_args *args);
u64 __seamcall_ret(u64 fn, struct tdx_module_args *args);
u64 __seamcall_saved_ret(u64 fn, struct tdx_module_args *args);
void tdx_init(void);
#include <asm/archrandom.h>
typedef u64 (*sc_func_t)(u64 fn, struct tdx_module_args *args);
static inline u64 sc_retry(sc_func_t func, u64 fn,
struct tdx_module_args *args)
{
int retry = RDRAND_RETRY_LOOPS;
u64 ret;
do {
ret = func(fn, args);
} while (ret == TDX_RND_NO_ENTROPY && --retry);
return ret;
}
#define seamcall(_fn, _args) sc_retry(__seamcall, (_fn), (_args))
#define seamcall_ret(_fn, _args) sc_retry(__seamcall_ret, (_fn), (_args))
#define seamcall_saved_ret(_fn, _args) sc_retry(__seamcall_saved_ret, (_fn), (_args))
int tdx_cpu_enable(void);
int tdx_enable(void);
const char *tdx_dump_mce_info(struct mce *m);
const struct tdx_sys_info *tdx_get_sysinfo(void);
int tdx_guest_keyid_alloc(void);
u32 tdx_get_nr_guest_keyids(void);
void tdx_guest_keyid_free(unsigned int keyid);
struct tdx_td {
/* TD root structure: */
struct page *tdr_page;
int tdcs_nr_pages;
/* TD control structure: */
struct page **tdcs_pages;
/* Size of `tdcx_pages` in struct tdx_vp */
int tdcx_nr_pages;
};
struct tdx_vp {
/* TDVP root page */
struct page *tdvpr_page;
/* TD vCPU control structure: */
struct page **tdcx_pages;
};
static inline u64 mk_keyed_paddr(u16 hkid, struct page *page)
{
u64 ret;
ret = page_to_phys(page);
/* KeyID bits are just above the physical address bits: */
ret |= (u64)hkid << boot_cpu_data.x86_phys_bits;
return ret;
}
static inline int pg_level_to_tdx_sept_level(enum pg_level level)
{
WARN_ON_ONCE(level == PG_LEVEL_NONE);
return level - 1;
}
u64 tdh_vp_enter(struct tdx_vp *vp, struct tdx_module_args *args);
u64 tdh_mng_addcx(struct tdx_td *td, struct page *tdcs_page);
u64 tdh_mem_page_add(struct tdx_td *td, u64 gpa, struct page *page, struct page *source, u64 *ext_err1, u64 *ext_err2);
u64 tdh_mem_sept_add(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2);
u64 tdh_vp_addcx(struct tdx_vp *vp, struct page *tdcx_page);
u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2);
u64 tdh_mem_range_block(struct tdx_td *td, u64 gpa, int level, u64 *ext_err1, u64 *ext_err2);
u64 tdh_mng_key_config(struct tdx_td *td);
u64 tdh_mng_create(struct tdx_td *td, u16 hkid);
u64 tdh_vp_create(struct tdx_td *td, struct tdx_vp *vp);
u64 tdh_mng_rd(struct tdx_td *td, u64 field, u64 *data);
u64 tdh_mr_extend(struct tdx_td *td, u64 gpa, u64 *ext_err1, u64 *ext_err2);
u64 tdh_mr_finalize(struct tdx_td *td);
u64 tdh_vp_flush(struct tdx_vp *vp);
u64 tdh_mng_vpflushdone(struct tdx_td *td);
u64 tdh_mng_key_freeid(struct tdx_td *td);
u64 tdh_mng_init(struct tdx_td *td, u64 td_params, u64 *extended_err);
u64 tdh_vp_init(struct tdx_vp *vp, u64 initial_rcx, u32 x2apicid);
u64 tdh_vp_rd(struct tdx_vp *vp, u64 field, u64 *data);
u64 tdh_vp_wr(struct tdx_vp *vp, u64 field, u64 data, u64 mask);
u64 tdh_phymem_page_reclaim(struct page *page, u64 *tdx_pt, u64 *tdx_owner, u64 *tdx_size);
u64 tdh_mem_track(struct tdx_td *tdr);
u64 tdh_mem_page_remove(struct tdx_td *td, u64 gpa, u64 level, u64 *ext_err1, u64 *ext_err2);
u64 tdh_phymem_cache_wb(bool resume);
u64 tdh_phymem_page_wbinvd_tdr(struct tdx_td *td);
u64 tdh_phymem_page_wbinvd_hkid(u64 hkid, struct page *page);
#else
static inline void tdx_init(void) { }
static inline int tdx_cpu_enable(void) { return -ENODEV; }
static inline int tdx_enable(void) { return -ENODEV; }
static inline u32 tdx_get_nr_guest_keyids(void) { return 0; }
static inline const char *tdx_dump_mce_info(struct mce *m) { return NULL; }
static inline const struct tdx_sys_info *tdx_get_sysinfo(void) { return NULL; }
#endif /* CONFIG_INTEL_TDX_HOST */
#endif /* !__ASSEMBLER__ */
#endif /* _ASM_X86_TDX_H */