Convert machine/elf.h, machine/frame.h, machine/sigframe.h,

machine/signal.h and machine/ucontext.h into common x86 includes,
copying from amd64 and merging with i386.

Kernel-only compat definitions are kept in the i386/include/sigframe.h
and i386/include/signal.h, to reduce amd64 kernel namespace pollution.
The amd64 compat uses its own definitions so far.

The _MACHINE_ELF_WANT_32BIT definition is to allow the
sys/boot/userboot/userboot/elf32_freebsd.c to use i386 ELF definitions
on the amd64 compile host.  The same hack could be usefully abused by
other code too.

5 files changed, 767 insertions, 0 deletions

diff --git a/sys/x86/include/elf.h b/sys/x86/include/elf.h
new file mode 100644
index 0000000..cde395b
--- /dev/null
+++ b/sys/x86/include/elf.h
@@ -0,0 +1,215 @@
+/*-
+ * Copyright (c) 1996-1997 John D. Polstra.
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _MACHINE_ELF_H_
+#define	_MACHINE_ELF_H_ 1
+
+#if defined(__i386__) || defined(_MACHINE_ELF_WANT_32BIT)
+
+/*
+ * ELF definitions for the i386 architecture.
+ */
+
+#include <sys/elf32.h>	/* Definitions common to all 32 bit architectures. */
+#if defined(__ELF_WORD_SIZE) && __ELF_WORD_SIZE == 64
+#include <sys/elf64.h>	/* Definitions common to all 64 bit architectures. */
+#endif
+
+#ifndef __ELF_WORD_SIZE
+#define	__ELF_WORD_SIZE	32	/* Used by <sys/elf_generic.h> */
+#endif
+
+#include <sys/elf_generic.h>
+
+#define	ELF_ARCH	EM_386
+
+#define	ELF_MACHINE_OK(x) ((x) == EM_386 || (x) == EM_486)
+
+/*
+ * Auxiliary vector entries for passing information to the interpreter.
+ *
+ * The i386 supplement to the SVR4 ABI specification names this "auxv_t",
+ * but POSIX lays claim to all symbols ending with "_t".
+ */
+
+typedef struct {	/* Auxiliary vector entry on initial stack */
+	int	a_type;			/* Entry type. */
+	union {
+		long	a_val;		/* Integer value. */
+		void	*a_ptr;		/* Address. */
+		void	(*a_fcn)(void);	/* Function pointer (not used). */
+	} a_un;
+} Elf32_Auxinfo;
+
+#if __ELF_WORD_SIZE == 64
+/* Fake for amd64 loader support */
+typedef struct {
+	int fake;
+} Elf64_Auxinfo;
+#endif
+
+__ElfType(Auxinfo);
+
+/* Values for a_type. */
+#define	AT_NULL		0	/* Terminates the vector. */
+#define	AT_IGNORE	1	/* Ignored entry. */
+#define	AT_EXECFD	2	/* File descriptor of program to load. */
+#define	AT_PHDR		3	/* Program header of program already loaded. */
+#define	AT_PHENT	4	/* Size of each program header entry. */
+#define	AT_PHNUM	5	/* Number of program header entries. */
+#define	AT_PAGESZ	6	/* Page size in bytes. */
+#define	AT_BASE		7	/* Interpreter's base address. */
+#define	AT_FLAGS	8	/* Flags (unused for i386). */
+#define	AT_ENTRY	9	/* Where interpreter should transfer control. */
+#define	AT_NOTELF	10	/* Program is not ELF ?? */
+#define	AT_UID		11	/* Real uid. */
+#define	AT_EUID		12	/* Effective uid. */
+#define	AT_GID		13	/* Real gid. */
+#define	AT_EGID		14	/* Effective gid. */
+#define	AT_EXECPATH	15	/* Path to the executable. */
+#define	AT_CANARY	16	/* Canary for SSP. */
+#define	AT_CANARYLEN	17	/* Length of the canary. */
+#define	AT_OSRELDATE	18	/* OSRELDATE. */
+#define	AT_NCPUS	19	/* Number of CPUs. */
+#define	AT_PAGESIZES	20	/* Pagesizes. */
+#define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
+#define	AT_TIMEKEEP	22	/* Pointer to timehands. */
+#define	AT_STACKPROT	23	/* Initial stack protection. */
+
+#define	AT_COUNT	24	/* Count of defined aux entry types. */
+
+/*
+ * Relocation types.
+ */
+
+#define	R_386_COUNT	38	/* Count of defined relocation types. */
+
+/* Define "machine" characteristics */
+#define	ELF_TARG_CLASS	ELFCLASS32
+#define	ELF_TARG_DATA	ELFDATA2LSB
+#define	ELF_TARG_MACH	EM_386
+#define	ELF_TARG_VER	1
+
+#define	ET_DYN_LOAD_ADDR 0x01001000
+
+#elif defined(__amd64__)
+
+/*
+ * ELF definitions for the AMD64 architecture.
+ */
+
+#ifndef __ELF_WORD_SIZE
+#define	__ELF_WORD_SIZE	64	/* Used by <sys/elf_generic.h> */
+#endif
+#include <sys/elf32.h>	/* Definitions common to all 32 bit architectures. */
+#include <sys/elf64.h>	/* Definitions common to all 64 bit architectures. */
+#include <sys/elf_generic.h>
+
+#define	ELF_ARCH	EM_X86_64
+#define	ELF_ARCH32	EM_386
+
+#define	ELF_MACHINE_OK(x) ((x) == EM_X86_64)
+
+/*
+ * Auxiliary vector entries for passing information to the interpreter.
+ *
+ * The i386 supplement to the SVR4 ABI specification names this "auxv_t",
+ * but POSIX lays claim to all symbols ending with "_t".
+ */
+typedef struct {	/* Auxiliary vector entry on initial stack */
+	int	a_type;			/* Entry type. */
+	union {
+		int	a_val;		/* Integer value. */
+	} a_un;
+} Elf32_Auxinfo;
+
+
+typedef struct {	/* Auxiliary vector entry on initial stack */
+	long	a_type;			/* Entry type. */
+	union {
+		long	a_val;		/* Integer value. */
+		void	*a_ptr;		/* Address. */
+		void	(*a_fcn)(void);	/* Function pointer (not used). */
+	} a_un;
+} Elf64_Auxinfo;
+
+__ElfType(Auxinfo);
+
+/* Values for a_type. */
+#define	AT_NULL		0	/* Terminates the vector. */
+#define	AT_IGNORE	1	/* Ignored entry. */
+#define	AT_EXECFD	2	/* File descriptor of program to load. */
+#define	AT_PHDR		3	/* Program header of program already loaded. */
+#define	AT_PHENT	4	/* Size of each program header entry. */
+#define	AT_PHNUM	5	/* Number of program header entries. */
+#define	AT_PAGESZ	6	/* Page size in bytes. */
+#define	AT_BASE		7	/* Interpreter's base address. */
+#define	AT_FLAGS	8	/* Flags (unused for i386). */
+#define	AT_ENTRY	9	/* Where interpreter should transfer control. */
+#define	AT_NOTELF	10	/* Program is not ELF ?? */
+#define	AT_UID		11	/* Real uid. */
+#define	AT_EUID		12	/* Effective uid. */
+#define	AT_GID		13	/* Real gid. */
+#define	AT_EGID		14	/* Effective gid. */
+#define	AT_EXECPATH	15	/* Path to the executable. */
+#define	AT_CANARY	16	/* Canary for SSP */
+#define	AT_CANARYLEN	17	/* Length of the canary. */
+#define	AT_OSRELDATE	18	/* OSRELDATE. */
+#define	AT_NCPUS	19	/* Number of CPUs. */
+#define	AT_PAGESIZES	20	/* Pagesizes. */
+#define	AT_PAGESIZESLEN	21	/* Number of pagesizes. */
+#define	AT_TIMEKEEP	22	/* Pointer to timehands. */
+#define	AT_STACKPROT	23	/* Initial stack protection. */
+
+#define	AT_COUNT	24	/* Count of defined aux entry types. */
+
+/*
+ * Relocation types.
+ */
+
+#define	R_X86_64_COUNT	24	/* Count of defined relocation types. */
+
+/* Define "machine" characteristics */
+#if __ELF_WORD_SIZE == 32
+#define ELF_TARG_CLASS  ELFCLASS32
+#else
+#define ELF_TARG_CLASS  ELFCLASS64
+#endif
+#define	ELF_TARG_DATA	ELFDATA2LSB
+#define	ELF_TARG_MACH	EM_X86_64
+#define	ELF_TARG_VER	1
+
+#if __ELF_WORD_SIZE == 32
+#define	ET_DYN_LOAD_ADDR 0x01001000
+#else
+#define	ET_DYN_LOAD_ADDR 0x01021000
+#endif
+
+#endif /* __i386__, __amd64__ */
+
+#endif /* !_MACHINE_ELF_H_ */
diff --git a/sys/x86/include/frame.h b/sys/x86/include/frame.h
new file mode 100644
index 0000000..a32ef7c
--- /dev/null
+++ b/sys/x86/include/frame.h
@@ -0,0 +1,148 @@
+/*-
+ * Copyright (c) 2003 Peter Wemm.
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * William Jolitz.
+ *
+ * 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.
+ * 4. 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.
+ *
+ *	from: @(#)frame.h	5.2 (Berkeley) 1/18/91
+ * $FreeBSD$
+ */
+
+#ifndef _MACHINE_FRAME_H_
+#define _MACHINE_FRAME_H_ 1
+
+/*
+ * System stack frames.
+ */
+
+#ifdef __i386__
+/*
+ * Exception/Trap Stack Frame
+ */
+
+struct trapframe {
+	int	tf_fs;
+	int	tf_es;
+	int	tf_ds;
+	int	tf_edi;
+	int	tf_esi;
+	int	tf_ebp;
+	int	tf_isp;
+	int	tf_ebx;
+	int	tf_edx;
+	int	tf_ecx;
+	int	tf_eax;
+	int	tf_trapno;
+	/* below portion defined in 386 hardware */
+	int	tf_err;
+	int	tf_eip;
+	int	tf_cs;
+	int	tf_eflags;
+	/* below only when crossing rings (e.g. user to kernel) */
+	int	tf_esp;
+	int	tf_ss;
+};
+
+/* Superset of trap frame, for traps from virtual-8086 mode */
+
+struct trapframe_vm86 {
+	int	tf_fs;
+	int	tf_es;
+	int	tf_ds;
+	int	tf_edi;
+	int	tf_esi;
+	int	tf_ebp;
+	int	tf_isp;
+	int	tf_ebx;
+	int	tf_edx;
+	int	tf_ecx;
+	int	tf_eax;
+	int	tf_trapno;
+	/* below portion defined in 386 hardware */
+	int	tf_err;
+	int	tf_eip;
+	int	tf_cs;
+	int	tf_eflags;
+	/* below only when crossing rings (e.g. user to kernel) */
+	int	tf_esp;
+	int	tf_ss;
+	/* below only when switching out of VM86 mode */
+	int	tf_vm86_es;
+	int	tf_vm86_ds;
+	int	tf_vm86_fs;
+	int	tf_vm86_gs;
+};
+#endif /* __i386__ */
+
+#ifdef __amd64__
+/*
+ * Exception/Trap Stack Frame
+ *
+ * The ordering of this is specifically so that we can take first 6
+ * the syscall arguments directly from the beginning of the frame.
+ */
+
+struct trapframe {
+	register_t	tf_rdi;
+	register_t	tf_rsi;
+	register_t	tf_rdx;
+	register_t	tf_rcx;
+	register_t	tf_r8;
+	register_t	tf_r9;
+	register_t	tf_rax;
+	register_t	tf_rbx;
+	register_t	tf_rbp;
+	register_t	tf_r10;
+	register_t	tf_r11;
+	register_t	tf_r12;
+	register_t	tf_r13;
+	register_t	tf_r14;
+	register_t	tf_r15;
+	uint32_t	tf_trapno;
+	uint16_t	tf_fs;
+	uint16_t	tf_gs;
+	register_t	tf_addr;
+	uint32_t	tf_flags;
+	uint16_t	tf_es;
+	uint16_t	tf_ds;
+	/* below portion defined in hardware */
+	register_t	tf_err;
+	register_t	tf_rip;
+	register_t	tf_cs;
+	register_t	tf_rflags;
+	register_t	tf_rsp;
+	register_t	tf_ss;
+};
+
+#define	TF_HASSEGS	0x1
+#define	TF_HASBASES	0x2
+#define	TF_HASFPXSTATE	0x4
+#endif /* __amd64__ */
+
+#endif /* _MACHINE_FRAME_H_ */
diff --git a/sys/x86/include/sigframe.h b/sys/x86/include/sigframe.h
new file mode 100644
index 0000000..972a78e
--- /dev/null
+++ b/sys/x86/include/sigframe.h
@@ -0,0 +1,72 @@
+/*-
+ * Copyright (c) 1999 Marcel Moolenaar
+ * 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 
+ *    in this position and unchanged.
+ * 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. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _X86_SIGFRAME_H_
+#define	_X86_SIGFRAME_H_
+
+/*
+ * Signal frames, arguments passed to application signal handlers.
+ */
+
+#ifdef __i386__
+struct sigframe {
+	/*
+	 * The first four members may be used by applications.
+	 *
+	 * NOTE: The 4th argument is undocumented, ill commented
+	 * on and seems to be somewhat BSD "standard".  Handlers
+	 * installed with sigvec may be using it.
+	 */
+	register_t	sf_signum;
+	register_t	sf_siginfo;	/* code or pointer to sf_si */
+	register_t	sf_ucontext;	/* points to sf_uc */
+	register_t	sf_addr;	/* undocumented 4th arg */
+
+	union {
+		__siginfohandler_t	*sf_action;
+		__sighandler_t		*sf_handler;
+	} sf_ahu;
+	ucontext_t	sf_uc;		/* = *sf_ucontext */
+	siginfo_t	sf_si;		/* = *sf_siginfo (SA_SIGINFO case) */
+};
+#endif /* __i386__ */
+
+#ifdef __amd64__
+struct sigframe {
+	union {
+		__siginfohandler_t	*sf_action;
+		__sighandler_t		*sf_handler;
+	} sf_ahu;
+	ucontext_t	sf_uc;		/* = *sf_ucontext */
+	siginfo_t	sf_si;		/* = *sf_siginfo (SA_SIGINFO case) */
+};
+#endif /* __amd64__ */
+
+#endif /* _X86_SIGFRAME_H_ */
diff --git a/sys/x86/include/signal.h b/sys/x86/include/signal.h
new file mode 100644
index 0000000..dee908f
--- /dev/null
+++ b/sys/x86/include/signal.h
@@ -0,0 +1,167 @@
+/*-
+ * Copyright (c) 1986, 1989, 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 2003 Peter Wemm.
+ *
+ * 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.
+ * 4. 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.
+ *
+ *	@(#)signal.h	8.1 (Berkeley) 6/11/93
+ * $FreeBSD$
+ */
+
+#ifndef _X86_SIGNAL_H
+#define	_X86_SIGNAL_H 1
+
+/*
+ * Machine-dependent signal definitions
+ */
+
+#include <sys/cdefs.h>
+#include <sys/_sigset.h>
+
+#if __BSD_VISIBLE
+#include <machine/trap.h>	/* codes for SIGILL, SIGFPE */
+#endif
+
+#ifdef __i386__
+typedef int sig_atomic_t;
+
+#if __BSD_VISIBLE
+struct sigcontext {
+	struct __sigset sc_mask;	/* signal mask to restore */
+	int	sc_onstack;		/* sigstack state to restore */
+	int	sc_gs;			/* machine state (struct trapframe) */
+	int	sc_fs;
+	int	sc_es;
+	int	sc_ds;
+	int	sc_edi;
+	int	sc_esi;
+	int	sc_ebp;
+	int	sc_isp;
+	int	sc_ebx;
+	int	sc_edx;
+	int	sc_ecx;
+	int	sc_eax;
+	int	sc_trapno;
+	int	sc_err;
+	int	sc_eip;
+	int	sc_cs;
+	int	sc_efl;
+	int	sc_esp;
+	int	sc_ss;
+	int	sc_len;			/* sizeof(mcontext_t) */
+	/*
+	 * See <machine/ucontext.h> and <machine/npx.h> for
+	 * the following fields.
+	 */
+	int	sc_fpformat;
+	int	sc_ownedfp;
+	int	sc_flags;
+	int	sc_fpstate[128] __aligned(16);
+
+	int	sc_fsbase;
+	int	sc_gsbase;
+
+	int	sc_xfpustate;
+	int	sc_xfpustate_len;
+
+	int	sc_spare2[4];
+};
+
+#define	sc_sp		sc_esp
+#define	sc_fp		sc_ebp
+#define	sc_pc		sc_eip
+#define	sc_ps		sc_efl
+#define	sc_eflags	sc_efl
+
+#endif /* __BSD_VISIBLE */
+#endif /* __i386__ */
+
+#ifdef __amd64__
+typedef long sig_atomic_t;
+
+#if __BSD_VISIBLE
+/*
+ * Information pushed on stack when a signal is delivered.
+ * This is used by the kernel to restore state following
+ * execution of the signal handler.  It is also made available
+ * to the handler to allow it to restore state properly if
+ * a non-standard exit is performed.
+ *
+ * The sequence of the fields/registers after sc_mask in struct
+ * sigcontext must match those in mcontext_t and struct trapframe.
+ */
+struct sigcontext {
+	struct __sigset sc_mask;	/* signal mask to restore */
+	long	sc_onstack;		/* sigstack state to restore */
+	long	sc_rdi;		/* machine state (struct trapframe) */
+	long	sc_rsi;
+	long	sc_rdx;
+	long	sc_rcx;
+	long	sc_r8;
+	long	sc_r9;
+	long	sc_rax;
+	long	sc_rbx;
+	long	sc_rbp;
+	long	sc_r10;
+	long	sc_r11;
+	long	sc_r12;
+	long	sc_r13;
+	long	sc_r14;
+	long	sc_r15;
+	int	sc_trapno;
+	short	sc_fs;
+	short	sc_gs;
+	long	sc_addr;
+	int	sc_flags;
+	short	sc_es;
+	short	sc_ds;
+	long	sc_err;
+	long	sc_rip;
+	long	sc_cs;
+	long	sc_rflags;
+	long	sc_rsp;
+	long	sc_ss;
+	long	sc_len;			/* sizeof(mcontext_t) */
+	/*
+	 * See <machine/ucontext.h> and <machine/fpu.h> for the following
+	 * fields.
+	 */
+	long	sc_fpformat;
+	long	sc_ownedfp;
+	long	sc_fpstate[64] __aligned(16);
+
+	long	sc_fsbase;
+	long	sc_gsbase;
+
+	long	sc_xfpustate;
+	long	sc_xfpustate_len;
+
+	long	sc_spare[4];
+};
+#endif /* __BSD_VISIBLE */
+#endif /* __amd64__ */
+
+#endif
diff --git a/sys/x86/include/ucontext.h b/sys/x86/include/ucontext.h
new file mode 100644
index 0000000..2173efd
--- /dev/null
+++ b/sys/x86/include/ucontext.h
@@ -0,0 +1,165 @@
+/*-
+ * Copyright (c) 2003 Peter Wemm
+ * Copyright (c) 1999 Marcel Moolenaar
+ * 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 
+ *    in this position and unchanged.
+ * 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. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _X86_UCONTEXT_H_
+#define	_X86_UCONTEXT_H_
+
+#ifdef __i386__
+/* Keep _MC_* values similar to amd64 */
+#define	_MC_HASSEGS	0x1
+#define	_MC_HASBASES	0x2
+#define	_MC_HASFPXSTATE	0x4
+#define	_MC_FLAG_MASK	(_MC_HASSEGS | _MC_HASBASES | _MC_HASFPXSTATE)
+
+typedef struct __mcontext {
+	/*
+	 * The definition of mcontext_t must match the layout of
+	 * struct sigcontext after the sc_mask member.  This is so
+	 * that we can support sigcontext and ucontext_t at the same
+	 * time.
+	 */
+	__register_t	mc_onstack;	/* XXX - sigcontext compat. */
+	__register_t	mc_gs;		/* machine state (struct trapframe) */
+	__register_t	mc_fs;
+	__register_t	mc_es;
+	__register_t	mc_ds;
+	__register_t	mc_edi;
+	__register_t	mc_esi;
+	__register_t	mc_ebp;
+	__register_t	mc_isp;
+	__register_t	mc_ebx;
+	__register_t	mc_edx;
+	__register_t	mc_ecx;
+	__register_t	mc_eax;
+	__register_t	mc_trapno;
+	__register_t	mc_err;
+	__register_t	mc_eip;
+	__register_t	mc_cs;
+	__register_t	mc_eflags;
+	__register_t	mc_esp;
+	__register_t	mc_ss;
+
+	int	mc_len;			/* sizeof(mcontext_t) */
+#define	_MC_FPFMT_NODEV		0x10000	/* device not present or configured */
+#define	_MC_FPFMT_387		0x10001
+#define	_MC_FPFMT_XMM		0x10002
+	int	mc_fpformat;
+#define	_MC_FPOWNED_NONE	0x20000	/* FP state not used */
+#define	_MC_FPOWNED_FPU		0x20001	/* FP state came from FPU */
+#define	_MC_FPOWNED_PCB		0x20002	/* FP state came from PCB */
+	int	mc_ownedfp;
+	__register_t mc_flags;
+	/*
+	 * See <machine/npx.h> for the internals of mc_fpstate[].
+	 */
+	int	mc_fpstate[128] __aligned(16);
+
+	__register_t mc_fsbase;
+	__register_t mc_gsbase;
+
+	__register_t mc_xfpustate;
+	__register_t mc_xfpustate_len;
+
+	int	mc_spare2[4];
+} mcontext_t;
+#endif /* __i386__ */
+
+#ifdef __amd64__
+/*
+ * mc_trapno bits. Shall be in sync with TF_XXX.
+ */
+#define	_MC_HASSEGS	0x1
+#define	_MC_HASBASES	0x2
+#define	_MC_HASFPXSTATE	0x4
+#define	_MC_FLAG_MASK	(_MC_HASSEGS | _MC_HASBASES | _MC_HASFPXSTATE)
+
+typedef struct __mcontext {
+	/*
+	 * The definition of mcontext_t must match the layout of
+	 * struct sigcontext after the sc_mask member.  This is so
+	 * that we can support sigcontext and ucontext_t at the same
+	 * time.
+	 */
+	__register_t	mc_onstack;	/* XXX - sigcontext compat. */
+	__register_t	mc_rdi;		/* machine state (struct trapframe) */
+	__register_t	mc_rsi;
+	__register_t	mc_rdx;
+	__register_t	mc_rcx;
+	__register_t	mc_r8;
+	__register_t	mc_r9;
+	__register_t	mc_rax;
+	__register_t	mc_rbx;
+	__register_t	mc_rbp;
+	__register_t	mc_r10;
+	__register_t	mc_r11;
+	__register_t	mc_r12;
+	__register_t	mc_r13;
+	__register_t	mc_r14;
+	__register_t	mc_r15;
+	__uint32_t	mc_trapno;
+	__uint16_t	mc_fs;
+	__uint16_t	mc_gs;
+	__register_t	mc_addr;
+	__uint32_t	mc_flags;
+	__uint16_t	mc_es;
+	__uint16_t	mc_ds;
+	__register_t	mc_err;
+	__register_t	mc_rip;
+	__register_t	mc_cs;
+	__register_t	mc_rflags;
+	__register_t	mc_rsp;
+	__register_t	mc_ss;
+
+	long	mc_len;			/* sizeof(mcontext_t) */
+
+#define	_MC_FPFMT_NODEV		0x10000	/* device not present or configured */
+#define	_MC_FPFMT_XMM		0x10002
+	long	mc_fpformat;
+#define	_MC_FPOWNED_NONE	0x20000	/* FP state not used */
+#define	_MC_FPOWNED_FPU		0x20001	/* FP state came from FPU */
+#define	_MC_FPOWNED_PCB		0x20002	/* FP state came from PCB */
+	long	mc_ownedfp;
+	/*
+	 * See <machine/fpu.h> for the internals of mc_fpstate[].
+	 */
+	long	mc_fpstate[64] __aligned(16);
+
+	__register_t	mc_fsbase;
+	__register_t	mc_gsbase;
+
+	__register_t	mc_xfpustate;
+	__register_t	mc_xfpustate_len;
+
+	long	mc_spare[4];
+} mcontext_t;
+#endif /* __amd64__ */
+
+#endif /* !_X86_UCONTEXT_H_ */