linux/arch/x86/kernel/asm-offsets.c
Kai Huang c641cfb5c1 x86/tdx: Make TDX_HYPERCALL asm similar to TDX_MODULE_CALL
Now the 'struct tdx_hypercall_args' and 'struct tdx_module_args' are
almost the same, and the TDX_HYPERCALL and TDX_MODULE_CALL asm macro
share similar code pattern too.  The __tdx_hypercall() and __tdcall()
should be unified to use the same assembly code.

As a preparation to unify them, simplify the TDX_HYPERCALL to make it
more like the TDX_MODULE_CALL.

The TDX_HYPERCALL takes the pointer of 'struct tdx_hypercall_args' as
function call argument, and does below extra things comparing to the
TDX_MODULE_CALL:

1) It sets RAX to 0 (TDG.VP.VMCALL leaf) internally;
2) It sets RCX to the (fixed) bitmap of shared registers internally;
3) It calls __tdx_hypercall_failed() internally (and panics) when the
   TDCALL instruction itself fails;
4) After TDCALL, it moves R10 to RAX to return the return code of the
   VMCALL leaf, regardless the '\ret' asm macro argument;

Firstly, change the TDX_HYPERCALL to take the same function call
arguments as the TDX_MODULE_CALL does: TDCALL leaf ID, and the pointer
to 'struct tdx_module_args'.  Then 1) and 2) can be moved to the
caller:

 - TDG.VP.VMCALL leaf ID can be passed via the function call argument;
 - 'struct tdx_module_args' is 'struct tdx_hypercall_args' + RCX, thus
   the bitmap of shared registers can be passed via RCX in the
   structure.

Secondly, to move 3) and 4) out of assembly, make the TDX_HYPERCALL
always save output registers to the structure.  The caller then can:

 - Call __tdx_hypercall_failed() when TDX_HYPERCALL returns error;
 - Return R10 in the structure as the return code of the VMCALL leaf;

With above changes, change the asm function from __tdx_hypercall() to
__tdcall_hypercall(), and reimplement __tdx_hypercall() as the C wrapper
of it.  This avoids having to add another wrapper of __tdx_hypercall()
(_tdx_hypercall() is already taken).

The __tdcall_hypercall() will be replaced with a __tdcall() variant
using TDX_MODULE_CALL in a later commit as the final goal is to have one
assembly to handle both TDCALL and TDVMCALL.

Currently, the __tdx_hypercall() asm is in '.noinstr.text'.  To keep
this unchanged, annotate __tdx_hypercall(), which is a C function now,
as 'noinstr'.

Remove the __tdx_hypercall_ret() as __tdx_hypercall() already does so.

Implement __tdx_hypercall() in tdx-shared.c so it can be shared with the
compressed code.

Opportunistically fix a checkpatch error complaining using space around
parenthesis '(' and ')' while moving the bitmap of shared registers to
<asm/shared/tdx.h>.

[ dhansen: quash new calls of __tdx_hypercall_ret() that showed up ]

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/0cbf25e7aee3256288045023a31f65f0cef90af4.1692096753.git.kai.huang%40intel.com
2023-09-12 16:28:13 -07:00

124 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Generate definitions needed by assembly language modules.
* This code generates raw asm output which is post-processed to extract
* and format the required data.
*/
#define COMPILE_OFFSETS
#include <linux/crypto.h>
#include <crypto/aria.h>
#include <linux/sched.h>
#include <linux/stddef.h>
#include <linux/hardirq.h>
#include <linux/suspend.h>
#include <linux/kbuild.h>
#include <asm/processor.h>
#include <asm/thread_info.h>
#include <asm/sigframe.h>
#include <asm/bootparam.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>
#include <asm/tdx.h>
#ifdef CONFIG_XEN
#include <xen/interface/xen.h>
#endif
#ifdef CONFIG_X86_32
# include "asm-offsets_32.c"
#else
# include "asm-offsets_64.c"
#endif
static void __used common(void)
{
BLANK();
OFFSET(TASK_threadsp, task_struct, thread.sp);
#ifdef CONFIG_STACKPROTECTOR
OFFSET(TASK_stack_canary, task_struct, stack_canary);
#endif
BLANK();
OFFSET(pbe_address, pbe, address);
OFFSET(pbe_orig_address, pbe, orig_address);
OFFSET(pbe_next, pbe, next);
#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
BLANK();
OFFSET(IA32_SIGCONTEXT_ax, sigcontext_32, ax);
OFFSET(IA32_SIGCONTEXT_bx, sigcontext_32, bx);
OFFSET(IA32_SIGCONTEXT_cx, sigcontext_32, cx);
OFFSET(IA32_SIGCONTEXT_dx, sigcontext_32, dx);
OFFSET(IA32_SIGCONTEXT_si, sigcontext_32, si);
OFFSET(IA32_SIGCONTEXT_di, sigcontext_32, di);
OFFSET(IA32_SIGCONTEXT_bp, sigcontext_32, bp);
OFFSET(IA32_SIGCONTEXT_sp, sigcontext_32, sp);
OFFSET(IA32_SIGCONTEXT_ip, sigcontext_32, ip);
BLANK();
OFFSET(IA32_RT_SIGFRAME_sigcontext, rt_sigframe_ia32, uc.uc_mcontext);
#endif
#ifdef CONFIG_XEN
BLANK();
OFFSET(XEN_vcpu_info_mask, vcpu_info, evtchn_upcall_mask);
OFFSET(XEN_vcpu_info_pending, vcpu_info, evtchn_upcall_pending);
OFFSET(XEN_vcpu_info_arch_cr2, vcpu_info, arch.cr2);
#endif
BLANK();
OFFSET(TDX_MODULE_rcx, tdx_module_args, rcx);
OFFSET(TDX_MODULE_rdx, tdx_module_args, rdx);
OFFSET(TDX_MODULE_r8, tdx_module_args, r8);
OFFSET(TDX_MODULE_r9, tdx_module_args, r9);
OFFSET(TDX_MODULE_r10, tdx_module_args, r10);
OFFSET(TDX_MODULE_r11, tdx_module_args, r11);
OFFSET(TDX_MODULE_r12, tdx_module_args, r12);
OFFSET(TDX_MODULE_r13, tdx_module_args, r13);
OFFSET(TDX_MODULE_r14, tdx_module_args, r14);
OFFSET(TDX_MODULE_r15, tdx_module_args, r15);
OFFSET(TDX_MODULE_rbx, tdx_module_args, rbx);
OFFSET(TDX_MODULE_rdi, tdx_module_args, rdi);
OFFSET(TDX_MODULE_rsi, tdx_module_args, rsi);
BLANK();
OFFSET(BP_scratch, boot_params, scratch);
OFFSET(BP_secure_boot, boot_params, secure_boot);
OFFSET(BP_loadflags, boot_params, hdr.loadflags);
OFFSET(BP_hardware_subarch, boot_params, hdr.hardware_subarch);
OFFSET(BP_version, boot_params, hdr.version);
OFFSET(BP_kernel_alignment, boot_params, hdr.kernel_alignment);
OFFSET(BP_init_size, boot_params, hdr.init_size);
OFFSET(BP_pref_address, boot_params, hdr.pref_address);
BLANK();
DEFINE(PTREGS_SIZE, sizeof(struct pt_regs));
/* TLB state for the entry code */
OFFSET(TLB_STATE_user_pcid_flush_mask, tlb_state, user_pcid_flush_mask);
/* Layout info for cpu_entry_area */
OFFSET(CPU_ENTRY_AREA_entry_stack, cpu_entry_area, entry_stack_page);
DEFINE(SIZEOF_entry_stack, sizeof(struct entry_stack));
DEFINE(MASK_entry_stack, (~(sizeof(struct entry_stack) - 1)));
/* Offset for fields in tss_struct */
OFFSET(TSS_sp0, tss_struct, x86_tss.sp0);
OFFSET(TSS_sp1, tss_struct, x86_tss.sp1);
OFFSET(TSS_sp2, tss_struct, x86_tss.sp2);
OFFSET(X86_top_of_stack, pcpu_hot, top_of_stack);
OFFSET(X86_current_task, pcpu_hot, current_task);
#ifdef CONFIG_CALL_DEPTH_TRACKING
OFFSET(X86_call_depth, pcpu_hot, call_depth);
#endif
#if IS_ENABLED(CONFIG_CRYPTO_ARIA_AESNI_AVX_X86_64)
/* Offset for fields in aria_ctx */
BLANK();
OFFSET(ARIA_CTX_enc_key, aria_ctx, enc_key);
OFFSET(ARIA_CTX_dec_key, aria_ctx, dec_key);
OFFSET(ARIA_CTX_rounds, aria_ctx, rounds);
#endif
}