xref: /illumos-gate/usr/src/uts/intel/sys/ucontext.h (revision a7cee4e9766ebda975dd156d1f10a70f51c242f0)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
24  * Copyright 2023 Oxide Computer Company
25  *
26  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
31 /*	  All Rights Reserved	*/
32 
33 #ifndef _SYS_UCONTEXT_H
34 #define	_SYS_UCONTEXT_H
35 
36 #include <sys/feature_tests.h>
37 
38 #include <sys/types.h>
39 #include <sys/mcontext.h>
40 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
41 #include <sys/signal.h>
42 #endif
43 
44 #ifdef	__cplusplus
45 extern "C" {
46 #endif
47 
48 /*
49  * Inclusion of <sys/signal.h> for sigset_t and stack_t definitions
50  * breaks XPG4v2 namespace.  Therefore we must duplicate the defines
51  * for these types here when we did not include <sys/signal.h> OR
52  * when <sys/signal.h> would not have declared them.
53  */
54 
55 /* Need sigset_t for ucontext below */
56 #ifndef	_SIGSET_T
57 #define	_SIGSET_T
58 typedef	struct {	/* signal set type */
59 	unsigned int	__sigbits[4];
60 } sigset_t;
61 #endif /* _SIGSET_T */
62 
63 /* Need stack_t for ucontext below */
64 #ifndef	_STACK_T
65 #define	_STACK_T
66 typedef	struct {
67 	void	*ss_sp;
68 	size_t	ss_size;
69 	int	ss_flags;
70 } stack_t;
71 #endif /* _STACK_T */
72 
73 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
74 typedef	struct ucontext ucontext_t;
75 #else
76 typedef	struct __ucontext ucontext_t;
77 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
78 
79 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
80 struct	ucontext {
81 #else
82 struct	__ucontext {
83 #endif
84 	unsigned long	uc_flags;
85 	ucontext_t	*uc_link;
86 	sigset_t	uc_sigmask;
87 	stack_t		uc_stack;
88 	mcontext_t	uc_mcontext;
89 	/*
90 	 * The first three entries have been borrowed by the lx brand right now.
91 	 * That should be consolidated into a single uc_brand entry with a
92 	 * UC_BRAND flag. Until such time, to help folks downstream who have the
93 	 * lx brand, we leave them as is.
94 	 */
95 	long		uc_filler[3];
96 	long		uc_xsave;
97 	long		uc_filler1;
98 };
99 
100 #if defined(_SYSCALL32)
101 
102 /* Kernel view of user ILP32 ucontext structure */
103 
104 typedef struct ucontext32 {
105 	uint32_t	uc_flags;
106 	caddr32_t	uc_link;
107 	sigset_t	uc_sigmask;
108 	stack32_t	uc_stack;
109 	mcontext32_t	uc_mcontext;
110 	int32_t		uc_filler[3];
111 	int32_t		uc_xsave;
112 	int32_t		uc_filler1;
113 } ucontext32_t;
114 
115 #if defined(_KERNEL)
116 extern void ucontext_nto32(const ucontext_t *src, ucontext32_t *dest);
117 extern void ucontext_32ton(const ucontext32_t *src, ucontext_t *dest);
118 #endif
119 
120 #endif	/* _SYSCALL32 */
121 
122 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
123 #define	GETCONTEXT	0
124 #define	SETCONTEXT	1
125 #define	GETUSTACK	2
126 #define	SETUSTACK	3
127 #define	GETCONTEXT_EXTD	4
128 
129 /*
130  * values for uc_flags
131  * these are implementation dependent flags, that should be hidden
132  * from the user interface, defining which elements of ucontext
133  * are valid, and should be restored on call to setcontext
134  */
135 
136 #define	UC_SIGMASK	0x01
137 #define	UC_STACK	0x02
138 #define	UC_CPU		0x04
139 #define	UC_MAU		0x08
140 #define	UC_FPU		UC_MAU
141 #define	UC_XSAVE	0x10
142 
143 #define	UC_MCONTEXT	(UC_CPU|UC_FPU)
144 
145 /*
146  * UC_ALL specifies the default context
147  */
148 
149 #define	UC_ALL		(UC_SIGMASK|UC_STACK|UC_MCONTEXT)
150 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
151 
152 #ifdef _KERNEL
153 /*
154  * This structure is the private header for the xsave data that we end up
155  * sending to the stack. This is basically our own compressed form. See,
156  * uts/intel/os/fpu.c for more information. To help maintain the private nature,
157  * this is unfortunately duplicated in the xsave tests. If you change this you
158  * must update test/os-tests/tests/xsave/xsave_util.h.
159  */
160 #define	UC_XSAVE_VERS	(('u' << 24) | ('c' << 16) | 0x01)
161 typedef struct uc_xsave {
162 	uint32_t ucx_vers;
163 	uint32_t ucx_len;
164 	uint64_t ucx_bv;
165 } uc_xsave_t;
166 
167 typedef enum {
168 	/*
169 	 * Do a boring old savecontext() where we assume that only the data
170 	 * structure that we're given must be filled in.
171 	 */
172 	SAVECTXT_F_NONE = 0,
173 	/*
174 	 * Indicate that we should treat the ucontext_t as having valid user
175 	 * pointers for copying out extended state. Currently this means that we
176 	 * treat the uc_xsave member as something that points to a user address.
177 	 */
178 	SAVECTXT_F_EXTD	= 1 << 0,
179 	/*
180 	 * This indicates that we shouldn't do normal copyout handling and need
181 	 * to actually avoid potentially triggering a watchpoint because we're
182 	 * probably in signal handling context.
183 	 */
184 	SAVECTXT_F_ONFAULT = 1 << 1
185 } savecontext_flags_t;
186 
187 int savecontext(ucontext_t *, const k_sigset_t *, savecontext_flags_t);
188 void restorecontext(ucontext_t *);
189 
190 #ifdef _SYSCALL32
191 extern int savecontext32(ucontext32_t *, const k_sigset_t *,
192     savecontext_flags_t);
193 #endif
194 #endif
195 
196 #ifdef	__cplusplus
197 }
198 #endif
199 
200 #endif /* _SYS_UCONTEXT_H */
201