xref: /illumos-gate/usr/src/uts/intel/sys/ucontext.h (revision ed093b41)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
 * Copyright 2023 Oxide Computer Company
 *
 * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved	*/

#ifndef _SYS_UCONTEXT_H
#define	_SYS_UCONTEXT_H

#include <sys/feature_tests.h>

#include <sys/types.h>
#include <sys/mcontext.h>
#if !defined(_XPG4_2) || defined(__EXTENSIONS__)
#include <sys/signal.h>
#endif

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * Inclusion of <sys/signal.h> for sigset_t and stack_t definitions
 * breaks XPG4v2 namespace.  Therefore we must duplicate the defines
 * for these types here when _XPG4_2 is defined.
 */

#if defined(_XPG4_2) && !defined(__EXTENSIONS__)
#ifndef	_SIGSET_T
#define	_SIGSET_T
typedef	struct {	/* signal set type */
	unsigned long	__sigbits[4];
} sigset_t;
#endif /* _SIGSET_T */

#ifndef	_STACK_T
#define	_STACK_T
typedef	struct {
	void	*ss_sp;
	size_t	ss_size;
	int	ss_flags;
} stack_t;
#endif /* _STACK_T */
#endif /* defined(_XPG4_2) && !defined(__EXTENSIONS__) */

#if !defined(_XPG4_2) || defined(__EXTENSIONS__)
typedef	struct ucontext ucontext_t;
#else
typedef	struct __ucontext ucontext_t;
#endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */

#if !defined(_XPG4_2) || defined(__EXTENSIONS__)
struct	ucontext {
#else
struct	__ucontext {
#endif
	unsigned long	uc_flags;
	ucontext_t	*uc_link;
	sigset_t	uc_sigmask;
	stack_t		uc_stack;
	mcontext_t	uc_mcontext;
	/*
	 * The first three entries have been borrowed by the lx brand right now.
	 * That should be consolidated into a single uc_brand entry with a
	 * UC_BRAND flag. Until such time, to help folks downstream who have the
	 * lx brand, we leave them as is.
	 */
	long		uc_filler[3];
	long		uc_xsave;
	long		uc_filler1;
};

#if defined(_SYSCALL32)

/* Kernel view of user ILP32 ucontext structure */

typedef struct ucontext32 {
	uint32_t	uc_flags;
	caddr32_t	uc_link;
	sigset_t	uc_sigmask;
	stack32_t	uc_stack;
	mcontext32_t	uc_mcontext;
	int32_t		uc_filler[3];
	int32_t		uc_xsave;
	int32_t		uc_filler1;
} ucontext32_t;

#if defined(_KERNEL)
extern void ucontext_nto32(const ucontext_t *src, ucontext32_t *dest);
extern void ucontext_32ton(const ucontext32_t *src, ucontext_t *dest);
#endif

#endif	/* _SYSCALL32 */

#if !defined(_XPG4_2) || defined(__EXTENSIONS__)
#define	GETCONTEXT	0
#define	SETCONTEXT	1
#define	GETUSTACK	2
#define	SETUSTACK	3
#define	GETCONTEXT_EXTD	4

/*
 * values for uc_flags
 * these are implementation dependent flags, that should be hidden
 * from the user interface, defining which elements of ucontext
 * are valid, and should be restored on call to setcontext
 */

#define	UC_SIGMASK	0x01
#define	UC_STACK	0x02
#define	UC_CPU		0x04
#define	UC_MAU		0x08
#define	UC_FPU		UC_MAU
#define	UC_XSAVE	0x10

#define	UC_MCONTEXT	(UC_CPU|UC_FPU)

/*
 * UC_ALL specifies the default context
 */

#define	UC_ALL		(UC_SIGMASK|UC_STACK|UC_MCONTEXT)
#endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */

#ifdef _KERNEL
/*
 * This structure is the private header for the xsave data that we end up
 * sending to the stack. This is basically our own compressed form. See,
 * uts/intel/os/fpu.c for more information. To help maintain the private nature,
 * this is unfortunately duplicated in the xsave tests. If you change this you
 * must update test/os-tests/tests/xsave/xsave_util.h.
 */
#define	UC_XSAVE_VERS	(('u' << 24) | ('c' << 16) | 0x01)
typedef struct uc_xsave {
	uint32_t ucx_vers;
	uint32_t ucx_len;
	uint64_t ucx_bv;
} uc_xsave_t;

typedef enum {
	/*
	 * Do a boring old savecontext() where we assume that only the data
	 * structure that we're given must be filled in.
	 */
	SAVECTXT_F_NONE = 0,
	/*
	 * Indicate that we should treat the ucontext_t as having valid user
	 * pointers for copying out extended state. Currently this means that we
	 * treat the uc_xsave member as something that points to a user address.
	 */
	SAVECTXT_F_EXTD	= 1 << 0,
	/*
	 * This indicates that we shouldn't do normal copyout handling and need
	 * to actually avoid potentially triggering a watchpoint because we're
	 * probably in signal handling context.
	 */
	SAVECTXT_F_ONFAULT = 1 << 1
} savecontext_flags_t;

int savecontext(ucontext_t *, const k_sigset_t *, savecontext_flags_t);
void restorecontext(ucontext_t *);

#ifdef _SYSCALL32
extern int savecontext32(ucontext32_t *, const k_sigset_t *,
    savecontext_flags_t);
#endif
#endif

#ifdef	__cplusplus
}
#endif

#endif /* _SYS_UCONTEXT_H */