/*-
 * Copyright (c) 2003 Peter Wemm
 * All rights reserved.
 *
 * Copyright (c) 2021 The FreeBSD Foundation
 *
 * Portions of this software were developed by Konstantin Belousov
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

#include <machine/asmacros.h>
#include <sys/syscall.h>

#include "ia32_assym.h"

        .text
/*
 * Signal trampoline, mapped as vdso into shared page, or copied to
 * top of user stack for old binaries.
 */
        ALIGN_TEXT
        .globl  __vdso_ia32_sigcode
__vdso_ia32_sigcode:
        .cfi_startproc
        .cfi_signal_frame
        .cfi_def_cfa    %esp, 0
#if 0
        .cfi_offset     %gs,  IA32_SIGF_UC + IA32_UC_GS
        .cfi_offset     %fs,  IA32_SIGF_UC + IA32_UC_FS
        .cfi_offset     %es,  IA32_SIGF_UC + IA32_UC_ES
        .cfi_offset     %ds,  IA32_SIGF_UC + IA32_UC_DS
#endif
        .cfi_offset     %edi, IA32_SIGF_UC + IA32_UC_EDI
        .cfi_offset     %esi, IA32_SIGF_UC + IA32_UC_ESI
        .cfi_offset     %ebp, IA32_SIGF_UC + IA32_UC_EBP
        .cfi_offset     %ebx, IA32_SIGF_UC + IA32_UC_EBX
        .cfi_offset     %edx, IA32_SIGF_UC + IA32_UC_EDX
        .cfi_offset     %ecx, IA32_SIGF_UC + IA32_UC_ECX
        .cfi_offset     %eax, IA32_SIGF_UC + IA32_UC_EAX
        .cfi_offset     %eip, IA32_SIGF_UC + IA32_UC_EIP
#if 0
        .cfi_offset     %cs,  IA32_SIGF_UC + IA32_UC_CS
        .cfi_offset     %flags, IA32_SIGF_UC + IA32_UC_EFLAGS
#endif
        .cfi_offset     %esp, IA32_SIGF_UC + IA32_UC_ESP
#if 0
        .cfi_offset     %ss,  IA32_SIGF_UC + IA32_UC_SS
        .cfi_offset     93 /* %fs.base */, IA32_SIGF_UC + IA32_UC_FSBASE
        .cfi_offset     94 /* %gs.base */, IA32_SIGF_UC + IA32_UC_GSBASE
#endif
        calll   *IA32_SIGF_HANDLER(%esp)
        leal    IA32_SIGF_UC(%esp),%eax /* get ucontext */
        pushl   %eax
        .cfi_def_cfa    %esp, 4
        movl    $SYS_sigreturn,%eax
        pushl   %eax                    /* junk to fake return addr. */
        .cfi_def_cfa    %esp, 8
        int     $0x80                   /* enter kernel with args */
                                        /* on stack */
1:
        jmp     1b
        .cfi_endproc

        ALIGN_TEXT
        .globl  __vdso_freebsd4_ia32_sigcode
__vdso_freebsd4_ia32_sigcode:
#ifdef COMPAT_FREEBSD4
        calll   *IA32_SIGF_HANDLER(%esp)
        leal    IA32_SIGF_UC4(%esp),%eax/* get ucontext */
        pushl   %eax
        movl    $344,%eax               /* 4.x SYS_sigreturn */
        pushl   %eax                    /* junk to fake return addr. */
        int     $0x80                   /* enter kernel with args */
                                        /* on stack */
1:
        jmp     1b
#else
        ud2
#endif

        ALIGN_TEXT
        .globl  __vdso_ia32_osigcode
__vdso_ia32_osigcode:
#ifdef COMPAT_43
        calll   *IA32_SIGF_HANDLER(%esp)/* call signal handler */
        leal    IA32_SIGF_SC(%esp),%eax /* get sigcontext */
        pushl   %eax
        movl    $103,%eax               /* 3.x SYS_sigreturn */
        pushl   %eax                    /* junk to fake return addr. */
        int     $0x80                   /* enter kernel with args */
1:
        jmp     1b
#else
        ud2
#endif

/*
 * Our lcall $7,$0 handler remains in user mode (ring 3), since lcalls
 * don't change the interrupt mask, so if this one went directly to the
 * kernel then there would be a window with interrupts enabled in kernel
 * mode, and all interrupt handlers would have to be almost as complicated
 * as the NMI handler to support this.
 *
 * Instead, convert the lcall to an int0x80 call.  The kernel does most
 * of the conversion by popping the lcall return values off the user
 * stack and returning to them instead of to here, except when the
 * conversion itself fails.  Adjusting the stack here is impossible for
 * vfork() and harder for other syscalls.
 */
        ALIGN_TEXT
        .globl  __vdso_lcall_tramp
__vdso_lcall_tramp:
#ifdef COMPAT_43
        int     $0x80
1:      jmp     1b
#else
        ud2
#endif
        .p2align 1