/* -*- mode: asm -*- */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1993 The Regents of the University of California.
* All rights reserved.
*
* Copyright (c) 2018 The FreeBSD Foundation
* All rights reserved.
*
* Portions of this software were developed by
* Konstantin Belousov <kib@FreeBSD.org> under sponsorship from
* the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(__i386__)
#include <i386/asmacros.h>
#else /* !__i386__ */
#ifndef _MACHINE_ASMACROS_H_
#define _MACHINE_ASMACROS_H_
#include <sys/cdefs.h>
/* XXX too much duplication in various asm*.h's. */
/*
* CNAME is used to manage the relationship between symbol names in C
* and the equivalent assembly language names. CNAME is given a name as
* it would be used in a C program. It expands to the equivalent assembly
* language name.
*/
#define CNAME(csym) csym
#define ALIGN_DATA .p2align 3 /* 8 byte alignment, zero filled */
#define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */
#define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */
#define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \
.type CNAME(name),@function; CNAME(name):
#define ENTRY(name) GEN_ENTRY(name)
#define ALTENTRY(name) GEN_ENTRY(name)
#define END(name) .size name, . - name
/*
* Convenience for adding frame pointers to hand-coded ASM. Useful for
* DTrace, HWPMC, and KDB.
*/
#define PUSH_FRAME_POINTER \
pushq %rbp ; \
movq %rsp, %rbp ;
#define POP_FRAME_POINTER \
popq %rbp
#ifdef LOCORE
/*
* Access per-CPU data.
*/
#define PCPU(member) %gs:PC_ ## member
#define PCPU_ADDR(member, reg) \
movq %gs:PC_PRVSPACE, reg ; \
addq $PC_ ## member, reg
/*
* Convenience macro for declaring interrupt entry points.
*/
#define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \
.type __CONCAT(X,name),@function; __CONCAT(X,name):
.macro SAVE_SEGS
movw %fs,TF_FS(%rsp)
movw %gs,TF_GS(%rsp)
movw %es,TF_ES(%rsp)
movw %ds,TF_DS(%rsp)
.endm
.macro MOVE_STACKS qw
.L.offset=0
.rept \qw
movq .L.offset(%rsp),%rdx
movq %rdx,.L.offset(%rax)
.L.offset=.L.offset+8
.endr
.endm
.macro PTI_UUENTRY has_err
movq PCPU(KCR3),%rax
movq %rax,%cr3
movq PCPU(RSP0),%rax
subq $PTI_SIZE - 8 * (1 - \has_err),%rax
MOVE_STACKS ((PTI_SIZE / 8) - 1 + \has_err)
movq %rax,%rsp
popq %rdx
popq %rax
.endm
.macro PTI_UENTRY has_err
swapgs
lfence
cmpq $~0,PCPU(UCR3)
je 1f
pushq %rax
pushq %rdx
PTI_UUENTRY \has_err
1:
.endm
.macro PTI_ENTRY name, contk, contu, has_err=0
ALIGN_TEXT
.globl X\name\()_pti
.type X\name\()_pti,@function
X\name\()_pti:
/* %rax, %rdx, and possibly err are not yet pushed */
testb $SEL_RPL_MASK,PTI_CS-PTI_ERR-((1-\has_err)*8)(%rsp)
jz \contk
PTI_UENTRY \has_err
jmp \contu
.endm
.macro PTI_INTRENTRY vec_name
SUPERALIGN_TEXT
.globl X\vec_name\()_pti
.type X\vec_name\()_pti,@function
X\vec_name\()_pti:
testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* err, %rax, %rdx not pushed */
jz .L\vec_name\()_u
PTI_UENTRY has_err=0
jmp .L\vec_name\()_u
.endm
.macro INTR_PUSH_FRAME vec_name
SUPERALIGN_TEXT
.globl X\vec_name
.type X\vec_name,@function
X\vec_name:
testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* come from kernel? */
jz .L\vec_name\()_u /* Yes, dont swapgs again */
swapgs
.L\vec_name\()_u:
lfence
subq $TF_RIP,%rsp /* skip dummy tf_err and tf_trapno */
movq %rdi,TF_RDI(%rsp)
movq %rsi,TF_RSI(%rsp)
movq %rdx,TF_RDX(%rsp)
movq %rcx,TF_RCX(%rsp)
movq %r8,TF_R8(%rsp)
movq %r9,TF_R9(%rsp)
movq %rax,TF_RAX(%rsp)
movq %rbx,TF_RBX(%rsp)
movq %rbp,TF_RBP(%rsp)
movq %r10,TF_R10(%rsp)
movq %r11,TF_R11(%rsp)
movq %r12,TF_R12(%rsp)
movq %r13,TF_R13(%rsp)
movq %r14,TF_R14(%rsp)
movq %r15,TF_R15(%rsp)
SAVE_SEGS
movl $TF_HASSEGS,TF_FLAGS(%rsp)
pushfq
andq $~(PSL_D|PSL_AC),(%rsp)
popfq
testb $SEL_RPL_MASK,TF_CS(%rsp) /* come from kernel ? */
jz 1f /* yes, leave PCB_FULL_IRET alone */
movq PCPU(CURPCB),%r8
andl $~PCB_FULL_IRET,PCB_FLAGS(%r8)
call handle_ibrs_entry
1:
.endm
.macro INTR_HANDLER vec_name
.text
PTI_INTRENTRY \vec_name
INTR_PUSH_FRAME \vec_name
.endm
.macro RESTORE_REGS
movq TF_RDI(%rsp),%rdi
movq TF_RSI(%rsp),%rsi
movq TF_RDX(%rsp),%rdx
movq TF_RCX(%rsp),%rcx
movq TF_R8(%rsp),%r8
movq TF_R9(%rsp),%r9
movq TF_RAX(%rsp),%rax
movq TF_RBX(%rsp),%rbx
movq TF_RBP(%rsp),%rbp
movq TF_R10(%rsp),%r10
movq TF_R11(%rsp),%r11
movq TF_R12(%rsp),%r12
movq TF_R13(%rsp),%r13
movq TF_R14(%rsp),%r14
movq TF_R15(%rsp),%r15
.endm
#ifdef KMSAN
/*
* The KMSAN runtime relies on a TLS block to track initialization and origin
* state for function parameters and return values. To keep this state
* consistent in the face of asynchronous kernel-mode traps, the runtime
* maintains a stack of blocks: when handling an exception or interrupt,
* kmsan_intr_enter() pushes the new block to be used until the handler is
* complete, at which point kmsan_intr_leave() restores the previous block.
*
* Thus, KMSAN_ENTER/LEAVE hooks are required only in handlers for events that
* may have happened while in kernel-mode. In particular, they are not required
* around amd64_syscall() or ast() calls. Otherwise, kmsan_intr_enter() can be
* called unconditionally, without distinguishing between entry from user-mode
* or kernel-mode.
*/
#define KMSAN_ENTER callq kmsan_intr_enter
#define KMSAN_LEAVE callq kmsan_intr_leave
#else
#define KMSAN_ENTER
#define KMSAN_LEAVE
#endif
#endif /* LOCORE */
#ifdef __STDC__
#define ELFNOTE(name, type, desctype, descdata...) \
.pushsection .note.name, "a", @note ; \
.align 4 ; \
.long 2f - 1f /* namesz */ ; \
.long 4f - 3f /* descsz */ ; \
.long type ; \
1:.asciz #name ; \
2:.align 4 ; \
3:desctype descdata ; \
4:.align 4 ; \
.popsection
#else /* !__STDC__, i.e. -traditional */
#define ELFNOTE(name, type, desctype, descdata) \
.pushsection .note.name, "a", @note ; \
.align 4 ; \
.long 2f - 1f /* namesz */ ; \
.long 4f - 3f /* descsz */ ; \
.long type ; \
1:.asciz "name" ; \
2:.align 4 ; \
3:desctype descdata ; \
4:.align 4 ; \
.popsection
#endif /* __STDC__ */
#endif /* !_MACHINE_ASMACROS_H_ */
#endif /* __i386__ */
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