OpenCloudOS-Kernel/arch/powerpc/include/asm/extable.h

45 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ARCH_POWERPC_EXTABLE_H
#define _ARCH_POWERPC_EXTABLE_H
/*
* The exception table consists of pairs of relative addresses: the first is
* the address of an instruction that is allowed to fault, and the second is
* the address at which the program should continue. 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.
*/
#define ARCH_HAS_RELATIVE_EXTABLE
#ifndef __ASSEMBLY__
struct exception_table_entry {
int insn;
int fixup;
};
static inline unsigned long extable_fixup(const struct exception_table_entry *x)
{
return (unsigned long)&x->fixup + x->fixup;
}
#endif
/*
* Helper macro for exception table entries
*/
#define EX_TABLE(_fault, _target) \
stringify_in_c(.section __ex_table,"a";)\
stringify_in_c(.balign 4;) \
stringify_in_c(.long (_fault) - . ;) \
stringify_in_c(.long (_target) - . ;) \
stringify_in_c(.previous)
#endif