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, we leave them as is.
  92          */
  93         long            uc_filler[3];
  94         long            uc_xsave;
  95         long            uc_filler1;
  96 };
  97 
  98 #if defined(_SYSCALL32)
  99 
 100 /* Kernel view of user ILP32 ucontext structure */
 101 
 102 typedef struct ucontext32 {
 103         uint32_t        uc_flags;
 104         caddr32_t       uc_link;
 105         sigset_t        uc_sigmask;
 106         stack32_t       uc_stack;
 107         mcontext32_t    uc_mcontext;
 108         int32_t         uc_filler[3];
 109         int32_t         uc_xsave;
 110         int32_t         uc_filler1;
 111 } ucontext32_t;
 112 
 113 #if defined(_KERNEL)
 114 extern void ucontext_nto32(const ucontext_t *src, ucontext32_t *dest);
 115 extern void ucontext_32ton(const ucontext32_t *src, ucontext_t *dest);
 116 #endif
 117 
 118 #endif  /* _SYSCALL32 */
 119 
 120 #if !defined(_XPG4_2) || defined(__EXTENSIONS__)
 121 #define GETCONTEXT      0
 122 #define SETCONTEXT      1
 123 #define GETUSTACK       2
 124 #define SETUSTACK       3
 125 #define GETCONTEXT_EXTD 4
 126 
 127 /*
 128  * values for uc_flags
 129  * these are implementation dependent flags, that should be hidden
 130  * from the user interface, defining which elements of ucontext
 131  * are valid, and should be restored on call to setcontext
 132  */
 133 
 134 #define UC_SIGMASK      0x01
 135 #define UC_STACK        0x02
 136 #define UC_CPU          0x04
 137 #define UC_MAU          0x08
 138 #define UC_FPU          UC_MAU
 139 #define UC_XSAVE        0x10
 140 
 141 #define UC_MCONTEXT     (UC_CPU|UC_FPU)
 142 
 143 /*
 144  * UC_ALL specifies the default context
 145  */
 146 
 147 #define UC_ALL          (UC_SIGMASK|UC_STACK|UC_MCONTEXT)
 148 #endif /* !defined(_XPG4_2) || defined(__EXTENSIONS__) */
 149 
 150 #ifdef _KERNEL
 151 /*
 152  * This structure is the private header for the xsave data that we end up
 153  * sending to the stack. This is basically our own compressed form. See,
 154  * uts/intel/os/fpu.c for more information.
 155  */
 156 #define UC_XSAVE_VERS   (('u' << 24) | ('c' << 16) | 0x01)
 157 typedef struct uc_xsave {
 158         uint32_t ucx_vers;
 159         uint32_t ucx_len;
 160         uint64_t ucx_bv;
 161 } uc_xsave_t;
 162 
 163 typedef enum {
 164         /*
 165          * Do a boring old savecontext() where we assume that only the data
 166          * structure that we're given must be filled in.
 167          */
 168         SAVECTXT_F_NONE = 0,
 169         /*
 170          * Indicate that we should treat the ucontext_t as having valid user
 171          * pointers for copying out extended state. Currently this means that we
 172          * treat the uc_xsave member as something that points to a user address.
 173          */
 174         SAVECTXT_F_EXTD = 1 << 0,
 175         /*
 176          * This indicates that we shouldn't do normal copyout handling and need
 177          * to actually avoid potentially triggering a watchpoint because we're
 178          * probably in signal handling context.
 179          */
 180         SAVECTXT_F_ONFAULT = 1 << 1
 181 } savecontext_flags_t;
 182 
 183 int savecontext(ucontext_t *, const k_sigset_t *, savecontext_flags_t);
 184 void restorecontext(ucontext_t *);
 185 
 186 #ifdef _SYSCALL32
 187 extern int savecontext32(ucontext32_t *, const k_sigset_t *,
 188     savecontext_flags_t);
 189 #endif
 190 #endif
 191 
 192 #ifdef  __cplusplus
 193 }
 194 #endif
 195 
 196 #endif /* _SYS_UCONTEXT_H */