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/*-
* Copyright (c) 2003 Peter Wemm
* All rights reserved.
*
* 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.
*
* $FreeBSD$
*/
#include "opt_compat.h"
#include <machine/asmacros.h>
#include <sys/syscall.h>
#include "ia32_assym.h"
.text
.code32
/*
* Signal trampoline, copied to top of user stack
* XXX may need to be MD to match backend sendsig handoff protocol
*/
ALIGN_TEXT
.globl ia32_sigcode
ia32_sigcode:
calll *IA32_SIGF_HANDLER(%esp)
leal IA32_SIGF_UC(%esp),%eax /* get ucontext */
pushl %eax
movl $SYS_sigreturn,%eax
pushl %eax /* junk to fake return addr. */
int $0x80 /* enter kernel with args */
/* on stack */
1:
jmp 1b
#ifdef COMPAT_FREEBSD4
ALIGN_TEXT
freebsd4_ia32_sigcode:
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
#endif
#ifdef COMPAT_43
ALIGN_TEXT
ia32_osigcode:
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
/*
* The lcall $7,$0 emulator cannot use the call gate that does an
* inter-privilege transition. The reason is that the call gate
* does not disable interrupts, and, before the swapgs is
* executed, we would have a window where the ring 0 code is
* executed with the wrong gsbase.
*
* Instead, set LDT descriptor 0 as code segment, which reflects
* the lcall $7,$0 back to ring 3 trampoline. The trampoline sets up
* the frame for int $0x80.
*/
ALIGN_TEXT
lcall_tramp:
cmpl $SYS_vfork,%eax
je 1f
pushl %ebp
movl %esp,%ebp
pushl 0x24(%ebp) /* arg 6 */
pushl 0x20(%ebp)
pushl 0x1c(%ebp)
pushl 0x18(%ebp)
pushl 0x14(%ebp)
pushl 0x10(%ebp) /* arg 1 */
subl $4,%esp /* gap */
int $0x80
leavel
lretl
1:
/*
* vfork handling is special and relies on the libc stub saving
* the return ip in %ecx. Also, we assume that the call was done
* with ucode32 selector in %cs.
*/
int $0x80
movl $0x33,4(%esp) /* GUCODE32_SEL | SEL_UPL */
movl %ecx,(%esp)
lretl
#endif
ALIGN_TEXT
esigcode:
.data
.globl sz_ia32_sigcode
sz_ia32_sigcode:
.long esigcode-ia32_sigcode
#ifdef COMPAT_FREEBSD4
.globl sz_freebsd4_ia32_sigcode
sz_freebsd4_ia32_sigcode:
.long esigcode-freebsd4_ia32_sigcode
#endif
#ifdef COMPAT_43
.globl sz_ia32_osigcode
sz_ia32_osigcode:
.long esigcode-ia32_osigcode
.globl sz_lcall_tramp
sz_lcall_tramp:
.long esigcode-lcall_tramp
#endif
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