1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_BUG_H
3 #define _ASM_POWERPC_BUG_H
4 #ifdef __KERNEL__
5 
6 #include <asm/asm-compat.h>
7 #include <asm/extable.h>
8 
9 #ifdef CONFIG_BUG
10 
11 #ifdef __ASSEMBLY__
12 #include <asm/asm-offsets.h>
13 #ifdef CONFIG_DEBUG_BUGVERBOSE
14 .macro __EMIT_BUG_ENTRY addr,file,line,flags
15 	 .section __bug_table,"aw"
16 5001:	 .4byte \addr - .
17 	 .4byte 5002f - .
18 	 .short \line, \flags
19 	 .org 5001b+BUG_ENTRY_SIZE
20 	 .previous
21 	 .section .rodata,"a"
22 5002:	 .asciz "\file"
23 	 .previous
24 .endm
25 #else
26 .macro __EMIT_BUG_ENTRY addr,file,line,flags
27 	 .section __bug_table,"aw"
28 5001:	 .4byte \addr - .
29 	 .short \flags
30 	 .org 5001b+BUG_ENTRY_SIZE
31 	 .previous
32 .endm
33 #endif /* verbose */
34 
35 .macro EMIT_WARN_ENTRY addr,file,line,flags
36 	EX_TABLE(\addr,\addr+4)
37 	__EMIT_BUG_ENTRY \addr,\file,\line,\flags
38 .endm
39 
40 .macro EMIT_BUG_ENTRY addr,file,line,flags
41 	.if \flags & 1 /* BUGFLAG_WARNING */
42 	.err /* Use EMIT_WARN_ENTRY for warnings */
43 	.endif
44 	__EMIT_BUG_ENTRY \addr,\file,\line,\flags
45 .endm
46 
47 #else /* !__ASSEMBLY__ */
48 /* _EMIT_BUG_ENTRY expects args %0,%1,%2,%3 to be FILE, LINE, flags and
49    sizeof(struct bug_entry), respectively */
50 #ifdef CONFIG_DEBUG_BUGVERBOSE
51 #define _EMIT_BUG_ENTRY				\
52 	".section __bug_table,\"aw\"\n"		\
53 	"2:	.4byte 1b - .\n"		\
54 	"	.4byte %0 - .\n"		\
55 	"	.short %1, %2\n"		\
56 	".org 2b+%3\n"				\
57 	".previous\n"
58 #else
59 #define _EMIT_BUG_ENTRY				\
60 	".section __bug_table,\"aw\"\n"		\
61 	"2:	.4byte 1b - .\n"		\
62 	"	.short %2\n"			\
63 	".org 2b+%3\n"				\
64 	".previous\n"
65 #endif
66 
67 #define BUG_ENTRY(insn, flags, ...)			\
68 	__asm__ __volatile__(				\
69 		"1:	" insn "\n"			\
70 		_EMIT_BUG_ENTRY				\
71 		: : "i" (__FILE__), "i" (__LINE__),	\
72 		  "i" (flags),				\
73 		  "i" (sizeof(struct bug_entry)),	\
74 		  ##__VA_ARGS__)
75 
76 #define WARN_ENTRY(insn, flags, label, ...)		\
77 	asm_volatile_goto(				\
78 		"1:	" insn "\n"			\
79 		EX_TABLE(1b, %l[label])			\
80 		_EMIT_BUG_ENTRY				\
81 		: : "i" (__FILE__), "i" (__LINE__),	\
82 		  "i" (flags),				\
83 		  "i" (sizeof(struct bug_entry)),	\
84 		  ##__VA_ARGS__ : : label)
85 
86 /*
87  * BUG_ON() and WARN_ON() do their best to cooperate with compile-time
88  * optimisations. However depending on the complexity of the condition
89  * some compiler versions may not produce optimal results.
90  */
91 
92 #define BUG() do {						\
93 	BUG_ENTRY("twi 31, 0, 0", 0);				\
94 	unreachable();						\
95 } while (0)
96 #define HAVE_ARCH_BUG
97 
98 #define __WARN_FLAGS(flags) do {				\
99 	__label__ __label_warn_on;				\
100 								\
101 	WARN_ENTRY("twi 31, 0, 0", BUGFLAG_WARNING | (flags), __label_warn_on); \
102 	unreachable();						\
103 								\
104 __label_warn_on:						\
105 	break;							\
106 } while (0)
107 
108 #ifdef CONFIG_PPC64
109 #define BUG_ON(x) do {						\
110 	if (__builtin_constant_p(x)) {				\
111 		if (x)						\
112 			BUG();					\
113 	} else {						\
114 		BUG_ENTRY(PPC_TLNEI " %4, 0", 0, "r" ((__force long)(x)));	\
115 	}							\
116 } while (0)
117 
118 #define WARN_ON(x) ({						\
119 	bool __ret_warn_on = false;				\
120 	do {							\
121 		if (__builtin_constant_p((x))) {		\
122 			if (!(x)) 				\
123 				break; 				\
124 			__WARN();				\
125 			__ret_warn_on = true;			\
126 		} else {					\
127 			__label__ __label_warn_on;		\
128 								\
129 			WARN_ENTRY(PPC_TLNEI " %4, 0",		\
130 				   BUGFLAG_WARNING | BUGFLAG_TAINT(TAINT_WARN),	\
131 				   __label_warn_on,		\
132 				   "r" ((__force long)(x)));	\
133 			break;					\
134 __label_warn_on:						\
135 			__ret_warn_on = true;			\
136 		}						\
137 	} while (0);						\
138 	unlikely(__ret_warn_on);				\
139 })
140 
141 #define HAVE_ARCH_BUG_ON
142 #define HAVE_ARCH_WARN_ON
143 #endif
144 
145 #endif /* __ASSEMBLY __ */
146 #else
147 #ifdef __ASSEMBLY__
148 .macro EMIT_BUG_ENTRY addr,file,line,flags
149 .endm
150 .macro EMIT_WARN_ENTRY addr,file,line,flags
151 .endm
152 #else /* !__ASSEMBLY__ */
153 #define _EMIT_BUG_ENTRY
154 #define _EMIT_WARN_ENTRY
155 #endif
156 #endif /* CONFIG_BUG */
157 
158 #include <asm-generic/bug.h>
159 
160 #ifndef __ASSEMBLY__
161 
162 struct pt_regs;
163 void hash__do_page_fault(struct pt_regs *);
164 void bad_page_fault(struct pt_regs *, int);
165 extern void _exception(int, struct pt_regs *, int, unsigned long);
166 extern void _exception_pkey(struct pt_regs *, unsigned long, int);
167 extern void die(const char *, struct pt_regs *, long);
168 void die_mce(const char *str, struct pt_regs *regs, long err);
169 extern bool die_will_crash(void);
170 extern void panic_flush_kmsg_start(void);
171 extern void panic_flush_kmsg_end(void);
172 #endif /* !__ASSEMBLY__ */
173 
174 #endif /* __KERNEL__ */
175 #endif /* _ASM_POWERPC_BUG_H */
176