1 /*
2 * Copyright (c) 2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * @OSF_COPYRIGHT@
30 */
31 /*
32 * Mach Operating System
33 * Copyright (c) 1991,1990 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 * Software Distribution Coordinator or [email protected]
49 * School of Computer Science
50 * Carnegie Mellon University
51 * Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56 /*
57 */
58
59 #ifndef _ARM_TRAP_H_
60 #define _ARM_TRAP_H_
61
62 /*
63 * Hardware trap vectors for ARM.
64 */
65
66 #define T_RESET 0
67 #define T_UNDEF 1
68 #define T_SWI 2
69 #define T_PREFETCH_ABT 3
70 #define T_DATA_ABT 4
71 #define T_IRQ 6
72 #define T_FIQ 7
73 #define T_PMU 8
74
75
76 #define TRAP_NAMES "reset", "undefined instruction", "software interrupt", \
77 "prefetch abort", "data abort", "irq interrupt", \
78 "fast interrupt", "perfmon"
79
80 /*
81 * Page-fault trap codes.
82 */
83 #define T_PF_PROT 0x1 /* protection violation */
84 #define T_PF_WRITE 0x2 /* write access */
85 #define T_PF_USER 0x4 /* from user state */
86
87 #if !defined(ASSEMBLER)
88 #if __OPTIMIZE__
89 __attribute__((cold, always_inline))
90 static inline void
ml_recoverable_trap(unsigned int code)91 ml_recoverable_trap(unsigned int code)
92 __attribute__((diagnose_if(!__builtin_constant_p(code), "code must be constant", "error")))
93 {
94 __asm__ volatile ("brk #%0" : : "i"(code));
95 }
96
97 __attribute__((cold, noreturn, always_inline))
98 static inline void
ml_fatal_trap(unsigned int code)99 ml_fatal_trap(unsigned int code)
100 __attribute__((diagnose_if(!__builtin_constant_p(code), "code must be constant", "error")))
101 {
102 __asm__ volatile ("brk #%0" : : "i"(code));
103 __builtin_unreachable();
104 }
105
106 __attribute__((cold, noreturn, always_inline))
107 static inline void
ml_fatal_trap_with_value(unsigned int code,unsigned long value)108 ml_fatal_trap_with_value(unsigned int code, unsigned long value)
109 __attribute__((diagnose_if(!__builtin_constant_p(code), "code must be constant", "error")))
110 {
111 #if __arm64__
112 register unsigned long long _value __asm__("x8") = (value);
113 #else
114 register unsigned long _value __asm__("r8") = (value);
115 #endif
116 __asm__ volatile ("brk #%[_code]"
117 : "=r"(_value)
118 : [_code] "i"(code)
119 , "0"(_value));
120 __builtin_unreachable();
121 }
122 #else
123 #define ml_recoverable_trap(code) \
124 __asm__ volatile ("brk #%0" : : "i"(code))
125 #define ml_fatal_trap(code) ({ \
126 __asm__ volatile ("brk #%0" : : "i"(code)); \
127 __builtin_unreachable(); \
128 })
129 /*
130 * for unoptimized builds, drop `value`,
131 * chances are the values are easy to debug anyway
132 */
133 #define ml_fatal_trap_with_value(code, value) ({ \
134 (void)(value); \
135 __asm__ volatile ("brk #%0" : : "i"(code)); \
136 __builtin_unreachable(); \
137 })
138 #endif
139
140 #if defined(XNU_KERNEL_PRIVATE)
141 /*
142 * Unfortunately brk instruction only takes constant, so we have to unroll all the
143 * cases and let compiler do the real work. ¯\_(ツ)_/¯
144 *
145 * Codegen should be clean due to inlining which enables constant-folding.
146 */
147 #define TRAP_CASE(code) \
148 case code: \
149 ml_fatal_trap(0x5500 + code);
150
151 #define TRAP_5CASES(code) \
152 TRAP_CASE(code) \
153 TRAP_CASE(code + 1) \
154 TRAP_CASE(code + 2) \
155 TRAP_CASE(code + 3) \
156 TRAP_CASE(code + 4)
157
158 /* For use by clang option -ftrap-function only */
159 __attribute__((cold, always_inline))
160 static inline void
ml_bound_chk_soft_trap(unsigned char code)161 ml_bound_chk_soft_trap(unsigned char code)
162 {
163 switch (code) {
164 /* 0 ~ 24 */
165 TRAP_5CASES(0)
166 TRAP_5CASES(5)
167 TRAP_5CASES(10)
168 TRAP_5CASES(15)
169 TRAP_5CASES(20)
170 case 25: /* Bound check */
171 /* code defined in kern/telemetry.h */
172 #if BOUND_CHECKS_DEBUG
173 /*
174 * ml_recoverable_trap ensures that we get a separate trap instruction
175 * for each compiler-added check, and in BOUND_CHECKS_DEBUG we use it
176 * with the the fatal 0x5500 trap code. This makes it easier to
177 * understand what failed when you develop at desk.
178 */
179 ml_recoverable_trap(0x5500 + 25);
180 #else /* BOUND_CHECKS_DEBUG */
181 ml_recoverable_trap(0xFF00 + 25);
182 #endif /* BOUND_CHECKS_DEBUG */
183 break;
184 default:
185 ml_fatal_trap(0x0);
186 }
187 }
188 #endif /* XNU_KERNEL_PRIVATE */
189 #endif /* !ASSEMBLER */
190
191 #endif /* _ARM_TRAP_H_ */
192