2026-01-29 22:25:33 +08:00

48 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_SW64_EXTABLE_H
#define _ASM_SW64_EXTABLE_H
/*
* About the exception table:
*
* - insn is a 32-bit pc-relative offset from the faulting insn.
* - nextinsn is a 16-bit offset off of the faulting instruction
* (not off of the *next* instruction as branches are).
* - errreg is the register in which to place -EFAULT.
* - valreg is the final target register for the load sequence
* and will be zeroed.
*
* Either errreg or valreg may be $31, in which case nothing happens.
*
* The exception fixup information "just so happens" to be arranged
* as in a MEM format instruction. This lets us emit our three
* values like so:
*
* lda valreg, nextinsn(errreg)
*
*/
struct exception_table_entry {
signed int insn;
union exception_fixup {
unsigned int unit;
struct {
signed int nextinsn : 16;
unsigned int errreg : 5;
unsigned int valreg : 5;
} bits;
} fixup;
};
#define ARCH_HAS_RELATIVE_EXTABLE
extern int fixup_exception(struct pt_regs *regs, unsigned long pc);
#define swap_ex_entry_fixup(a, b, tmp, delta) \
do { \
(a)->fixup.unit = (b)->fixup.unit; \
(b)->fixup.unit = (tmp).fixup.unit; \
} while (0)
#endif /* _ASM_SW64_EXTABLE_H */