xref: /openbmc/linux/arch/arm64/include/asm/extable.h (revision 52cdded0)
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 
18 struct exception_table_entry
19 {
20 	int insn, fixup;
21 };
22 
23 #define ARCH_HAS_RELATIVE_EXTABLE
24 
25 #ifdef CONFIG_BPF_JIT
26 int arm64_bpf_fixup_exception(const struct exception_table_entry *ex,
27 			      struct pt_regs *regs);
28 #else /* !CONFIG_BPF_JIT */
29 static inline
30 int arm64_bpf_fixup_exception(const struct exception_table_entry *ex,
31 			      struct pt_regs *regs)
32 {
33 	return 0;
34 }
35 #endif /* !CONFIG_BPF_JIT */
36 
37 extern int fixup_exception(struct pt_regs *regs);
38 #endif
39