1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun #ifndef _ASM_X86_EXTABLE_H 3*4882a593Smuzhiyun #define _ASM_X86_EXTABLE_H 4*4882a593Smuzhiyun /* 5*4882a593Smuzhiyun * The exception table consists of triples of addresses relative to the 6*4882a593Smuzhiyun * exception table entry itself. The first address is of an instruction 7*4882a593Smuzhiyun * that is allowed to fault, the second is the target at which the program 8*4882a593Smuzhiyun * should continue. The third is a handler function to deal with the fault 9*4882a593Smuzhiyun * caused by the instruction in the first field. 10*4882a593Smuzhiyun * 11*4882a593Smuzhiyun * All the routines below use bits of fixup code that are out of line 12*4882a593Smuzhiyun * with the main instruction path. This means when everything is well, 13*4882a593Smuzhiyun * we don't even have to jump over them. Further, they do not intrude 14*4882a593Smuzhiyun * on our cache or tlb entries. 15*4882a593Smuzhiyun */ 16*4882a593Smuzhiyun 17*4882a593Smuzhiyun struct exception_table_entry { 18*4882a593Smuzhiyun int insn, fixup, handler; 19*4882a593Smuzhiyun }; 20*4882a593Smuzhiyun struct pt_regs; 21*4882a593Smuzhiyun 22*4882a593Smuzhiyun #define ARCH_HAS_RELATIVE_EXTABLE 23*4882a593Smuzhiyun 24*4882a593Smuzhiyun #define swap_ex_entry_fixup(a, b, tmp, delta) \ 25*4882a593Smuzhiyun do { \ 26*4882a593Smuzhiyun (a)->fixup = (b)->fixup + (delta); \ 27*4882a593Smuzhiyun (b)->fixup = (tmp).fixup - (delta); \ 28*4882a593Smuzhiyun (a)->handler = (b)->handler + (delta); \ 29*4882a593Smuzhiyun (b)->handler = (tmp).handler - (delta); \ 30*4882a593Smuzhiyun } while (0) 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun enum handler_type { 33*4882a593Smuzhiyun EX_HANDLER_NONE, 34*4882a593Smuzhiyun EX_HANDLER_FAULT, 35*4882a593Smuzhiyun EX_HANDLER_UACCESS, 36*4882a593Smuzhiyun EX_HANDLER_OTHER 37*4882a593Smuzhiyun }; 38*4882a593Smuzhiyun 39*4882a593Smuzhiyun extern int fixup_exception(struct pt_regs *regs, int trapnr, 40*4882a593Smuzhiyun unsigned long error_code, unsigned long fault_addr); 41*4882a593Smuzhiyun extern int fixup_bug(struct pt_regs *regs, int trapnr); 42*4882a593Smuzhiyun extern enum handler_type ex_get_fault_handler_type(unsigned long ip); 43*4882a593Smuzhiyun extern void early_fixup_exception(struct pt_regs *regs, int trapnr); 44*4882a593Smuzhiyun 45*4882a593Smuzhiyun #endif 46