linux-zen-desktop/arch/s390/include/asm/extable.h

73 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __S390_EXTABLE_H
#define __S390_EXTABLE_H
#include <asm/ptrace.h>
#include <linux/compiler.h>
/*
* The exception table consists of three addresses:
*
* - Address of an instruction that is allowed to fault.
* - Address at which the program should continue.
* - Optional address of handler that takes pt_regs * argument and runs in
* interrupt context.
*
* No registers are modified, so it is entirely up to the continuation code
* to figure out what to do.
*
* All the routines below use bits of fixup code that are out of line
* with the main instruction path. This means when everything is well,
* we don't even have to jump over them. Further, they do not intrude
* on our cache or tlb entries.
*/
struct exception_table_entry
{
int insn, fixup;
short type, data;
};
extern struct exception_table_entry *__start_amode31_ex_table;
extern struct exception_table_entry *__stop_amode31_ex_table;
const struct exception_table_entry *s390_search_extables(unsigned long addr);
static inline unsigned long extable_fixup(const struct exception_table_entry *x)
{
return (unsigned long)&x->fixup + x->fixup;
}
#define ARCH_HAS_RELATIVE_EXTABLE
static inline void swap_ex_entry_fixup(struct exception_table_entry *a,
struct exception_table_entry *b,
struct exception_table_entry tmp,
int delta)
{
a->fixup = b->fixup + delta;
b->fixup = tmp.fixup - delta;
a->type = b->type;
b->type = tmp.type;
a->data = b->data;
b->data = tmp.data;
}
#define swap_ex_entry_fixup swap_ex_entry_fixup
#ifdef CONFIG_BPF_JIT
bool ex_handler_bpf(const struct exception_table_entry *ex, struct pt_regs *regs);
#else /* !CONFIG_BPF_JIT */
static inline bool ex_handler_bpf(const struct exception_table_entry *ex, struct pt_regs *regs)
{
return false;
}
#endif /* CONFIG_BPF_JIT */
bool fixup_exception(struct pt_regs *regs);
#endif