arch/s390/include/asm/extable.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __S390_EXTABLE_H
   3 #define __S390_EXTABLE_H
   4 /*
   5  * The exception table consists of pairs of addresses: the first is the
   6  * address of an instruction that is allowed to fault, and the second is
   7  * the address at which the program should continue.  No registers are
   8  * modified, so it is entirely up to the continuation code to figure out
   9  * what to do.
  10  *
  11  * All the routines below use bits of fixup code that are out of line
  12  * with the main instruction path.  This means when everything is well,
  13  * we don't even have to jump over them.  Further, they do not intrude
  14  * on our cache or tlb entries.
  15  */
  16
  17 struct exception_table_entry
  18 {
  19         int insn, fixup;
  20 };
  21
  22 extern struct exception_table_entry *__start_dma_ex_table;
  23 extern struct exception_table_entry *__stop_dma_ex_table;
  24
  25 const struct exception_table_entry *s390_search_extables(unsigned long addr);
  26
  27 static inline unsigned long extable_fixup(const struct exception_table_entry *x)
  28 {
  29         return (unsigned long)&x->fixup + x->fixup;
  30 }
  31
  32 #define ARCH_HAS_RELATIVE_EXTABLE
  33
  34 #endif