linux-stable/arch/x86/include/asm/extable.h
Tony Luck a05d54c41e x86/mce: Provide method to find out the type of an exception handler
Avoid a proliferation of ex_has_*_handler() functions by having just
one function that returns the type of the handler (if any).

Drop the __visible attribute for this function. It is not called
from assembler so the attribute is not necessary.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201006210910.21062-3-tony.luck@intel.com
2020-10-07 11:08:59 +02:00

45 lines
1.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_EXTABLE_H
#define _ASM_X86_EXTABLE_H
/*
* The exception table consists of triples of addresses relative to the
* exception table entry itself. The first address is of an instruction
* that is allowed to fault, the second is the target at which the program
* should continue. The third is a handler function to deal with the fault
* caused by the instruction in the first field.
*
* 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, handler;
};
struct pt_regs;
#define ARCH_HAS_RELATIVE_EXTABLE
#define swap_ex_entry_fixup(a, b, tmp, delta) \
do { \
(a)->fixup = (b)->fixup + (delta); \
(b)->fixup = (tmp).fixup - (delta); \
(a)->handler = (b)->handler + (delta); \
(b)->handler = (tmp).handler - (delta); \
} while (0)
enum handler_type {
EX_HANDLER_NONE,
EX_HANDLER_FAULT,
EX_HANDLER_UACCESS,
EX_HANDLER_OTHER
};
extern int fixup_exception(struct pt_regs *regs, int trapnr,
unsigned long error_code, unsigned long fault_addr);
extern int fixup_bug(struct pt_regs *regs, int trapnr);
extern enum handler_type ex_get_fault_handler_type(unsigned long ip);
extern void early_fixup_exception(struct pt_regs *regs, int trapnr);
#endif