xref: /illumos-gate/usr/src/uts/intel/sys/ucontext.h (revision 533affcbc7fc4d0c8132976ea454aaa715fe2307)
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 _XPG4_2 is defined.
52  */
53 
54 #if defined(_XPG4_2) && !defined(__EXTENSIONS__)
55 #ifndef	_SIGSET_T
56 #define	_SIGSET_T
57 typedef	struct {	/* signal set type */
58 	unsigned long	__sigbits[4];
59 } sigset_t;
60 #endif /* _SIGSET_T */
61 
62 #ifndef	_STACK_T
63 #define	_STACK_T
64 typedef	struct {
65 	void	*ss_sp;
66 	size_t	ss_size;
67 	int	ss_flags;
68 } stack_t;
69 #endif /* _STACK_T */
70 #endif /* defined(_XPG4_2) && !defined(__EXTENSIONS__) */
71 
72 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
73 typedef	struct ucontext ucontext_t;
74 #else
75 typedef	struct __ucontext ucontext_t;
76 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
77 
78 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
79 struct	ucontext {
80 #else
81 struct	__ucontext {
82 #endif
83 	unsigned long	uc_flags;
84 	ucontext_t	*uc_link;
85 	sigset_t	uc_sigmask;
86 	stack_t		uc_stack;
87 	mcontext_t	uc_mcontext;
88 	/*
89 	 * The first three entries have been borrowed by the lx brand right now.
90 	 * That should be consolidated into a single uc_brand entry with a
91 	 * UC_BRAND flag. Until such time, to help folks downstream who have the
92 	 * lx brand, we leave them as is.
93 	 */
94 	long		uc_filler[3];
95 	long		uc_xsave;
96 	long		uc_filler1;
97 };
98 
99 #if defined(_SYSCALL32)
100 
101 /* Kernel view of user ILP32 ucontext structure */
102 
103 typedef struct ucontext32 {
104 	uint32_t	uc_flags;
105 	caddr32_t	uc_link;
106 	sigset_t	uc_sigmask;
107 	stack32_t	uc_stack;
108 	mcontext32_t	uc_mcontext;
109 	int32_t		uc_filler[3];
110 	int32_t		uc_xsave;
111 	int32_t		uc_filler1;
112 } ucontext32_t;
113 
114 #if defined(_KERNEL)
115 extern void ucontext_nto32(const ucontext_t *src, ucontext32_t *dest);
116 extern void ucontext_32ton(const ucontext32_t *src, ucontext_t *dest);
117 #endif
118 
119 #endif	/* _SYSCALL32 */
120 
121 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
122 #define	GETCONTEXT	0
123 #define	SETCONTEXT	1
124 #define	GETUSTACK	2
125 #define	SETUSTACK	3
126 #define	GETCONTEXT_EXTD	4
127 
128 /*
129  * values for uc_flags
130  * these are implementation dependent flags, that should be hidden
131  * from the user interface, defining which elements of ucontext
132  * are valid, and should be restored on call to setcontext
133  */
134 
135 #define	UC_SIGMASK	0x01
136 #define	UC_STACK	0x02
137 #define	UC_CPU		0x04
138 #define	UC_MAU		0x08
139 #define	UC_FPU		UC_MAU
140 #define	UC_XSAVE	0x10
141 
142 #define	UC_MCONTEXT	(UC_CPU|UC_FPU)
143 
144 /*
145  * UC_ALL specifies the default context
146  */
147 
148 #define	UC_ALL		(UC_SIGMASK|UC_STACK|UC_MCONTEXT)
149 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
150 
151 #ifdef _KERNEL
152 /*
153  * This structure is the private header for the xsave data that we end up
154  * sending to the stack. This is basically our own compressed form. See,
155  * uts/intel/os/fpu.c for more information. To help maintain the private nature,
156  * this is unfortunately duplicated in the xsave tests. If you change this you
157  * must update test/os-tests/tests/xsave/xsave_util.h.
158  */
159 #define	UC_XSAVE_VERS	(('u' << 24) | ('c' << 16) | 0x01)
160 typedef struct uc_xsave {
161 	uint32_t ucx_vers;
162 	uint32_t ucx_len;
163 	uint64_t ucx_bv;
164 } uc_xsave_t;
165 
166 typedef enum {
167 	/*
168 	 * Do a boring old savecontext() where we assume that only the data
169 	 * structure that we're given must be filled in.
170 	 */
171 	SAVECTXT_F_NONE = 0,
172 	/*
173 	 * Indicate that we should treat the ucontext_t as having valid user
174 	 * pointers for copying out extended state. Currently this means that we
175 	 * treat the uc_xsave member as something that points to a user address.
176 	 */
177 	SAVECTXT_F_EXTD	= 1 << 0,
178 	/*
179 	 * This indicates that we shouldn't do normal copyout handling and need
180 	 * to actually avoid potentially triggering a watchpoint because we're
181 	 * probably in signal handling context.
182 	 */
183 	SAVECTXT_F_ONFAULT = 1 << 1
184 } savecontext_flags_t;
185 
186 int savecontext(ucontext_t *, const k_sigset_t *, savecontext_flags_t);
187 void restorecontext(ucontext_t *);
188 
189 #ifdef _SYSCALL32
190 extern int savecontext32(ucontext32_t *, const k_sigset_t *,
191     savecontext_flags_t);
192 #endif
193 #endif
194 
195 #ifdef	__cplusplus
196 }
197 #endif
198 
199 #endif /* _SYS_UCONTEXT_H */
200