1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __S390_EXTABLE_H
3 #define __S390_EXTABLE_H
4 /*
5 * The exception table consists of pairs of addresses: the first is the
6 * address of an instruction that is allowed to fault, and the second is
7 * the address at which the program should continue. No registers are
8 * modified, so it is entirely up to the continuation code to figure out
9 * what to do.
10 *
11 * All the routines below use bits of fixup code that are out of line
12 * with the main instruction path. This means when everything is well,
13 * we don't even have to jump over them. Further, they do not intrude
14 * on our cache or tlb entries.
15 */
16
17 struct exception_table_entry
18 {
19 int insn, fixup;
20 };
21
22 extern struct exception_table_entry *__start_dma_ex_table;
23 extern struct exception_table_entry *__stop_dma_ex_table;
24
25 const struct exception_table_entry *s390_search_extables(unsigned long addr);
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 #define ARCH_HAS_RELATIVE_EXTABLE
33
34 #endif