arch/x86/include/asm/extable.h

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