1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef __ASM_EXTABLE_H
 3#define __ASM_EXTABLE_H
 4
 5/*
 6 * The exception table consists of pairs of relative offsets: the first
 7 * is the relative offset to an instruction that is allowed to fault,
 8 * and the second is the relative offset at which the program should
 9 * continue. No registers are modified, so it is entirely up to the
10 * continuation code to figure out what to do.
11 *
12 * All the routines below use bits of fixup code that are out of line
13 * with the main instruction path.  This means when everything is well,
14 * we don't even have to jump over them.  Further, they do not intrude
15 * on our cache or tlb entries.
16 */
17
18struct exception_table_entry
19{
20	int insn, fixup;
21	short type, data;
22};
23
24#define ARCH_HAS_RELATIVE_EXTABLE
25
26#define swap_ex_entry_fixup(a, b, tmp, delta)		\
27do {							\
28	(a)->fixup = (b)->fixup + (delta);		\
29	(b)->fixup = (tmp).fixup - (delta);		\
30	(a)->type = (b)->type;				\
31	(b)->type = (tmp).type;				\
32	(a)->data = (b)->data;				\
33	(b)->data = (tmp).data;				\
34} while (0)
35
36#ifdef CONFIG_BPF_JIT
37bool ex_handler_bpf(const struct exception_table_entry *ex,
38		    struct pt_regs *regs);
39#else /* !CONFIG_BPF_JIT */
40static inline
41bool ex_handler_bpf(const struct exception_table_entry *ex,
42		    struct pt_regs *regs)
43{
44	return false;
45}
46#endif /* !CONFIG_BPF_JIT */
47
48bool fixup_exception(struct pt_regs *regs);
49#endif