1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ARCH_POWERPC_EXTABLE_H
3 #define _ARCH_POWERPC_EXTABLE_H
4
5 /*
6 * The exception table consists of pairs of relative addresses: the first is
7 * the address of an instruction that is allowed to fault, and the second is
8 * the address at which the program should continue. No registers are
9 * modified, so it is entirely up to the continuation code to figure out what
10 * to do.
11 *
12 * All the routines below use bits of fixup code that are out of line with the
13 * main instruction path. This means when everything is well, we don't even
14 * have to jump over them. Further, they do not intrude on our cache or tlb
15 * entries.
16 */
17
18 #define ARCH_HAS_RELATIVE_EXTABLE
19
20 #ifndef __ASSEMBLY__
21
22 struct exception_table_entry {
23 int insn;
24 int fixup;
25 };
26
27 static inline unsigned long extable_fixup(const struct exception_table_entry *x)
28 {
29 return (unsigned long)&x->fixup + x->fixup;
30 }
31
32 #endif
33
34 /*
35 * Helper macro for exception table entries
36 */
37 #define EX_TABLE(_fault, _target) \
38 stringify_in_c(.section __ex_table,"a";)\
39 stringify_in_c(.balign 4;) \
40 stringify_in_c(.long (_fault) - . ;) \
41 stringify_in_c(.long (_target) - . ;) \
42 stringify_in_c(.previous)
43
44 #endif
45
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.