LXR linux/arch/powerpc/include/asm/jump

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2#ifndef _ASM_POWERPC_JUMP_LABEL_H
   3#define _ASM_POWERPC_JUMP_LABEL_H
   4
   5/*
   6 * Copyright 2010 Michael Ellerman, IBM Corp.
   7 */
   8
   9#ifndef __ASSEMBLY__
  10#include <linux/types.h>
  11
  12#include <asm/feature-fixups.h>
  13#include <asm/asm-const.h>
  14
  15#define JUMP_ENTRY_TYPE         stringify_in_c(FTR_ENTRY_LONG)
  16#define JUMP_LABEL_NOP_SIZE     4
  17
  18static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
  19{
  20        asm_volatile_goto("1:\n\t"
  21                 "nop # arch_static_branch\n\t"
  22                 ".pushsection __jump_table,  \"aw\"\n\t"
  23                 ".long 1b - ., %l[l_yes] - .\n\t"
  24                 JUMP_ENTRY_TYPE "%c0 - .\n\t"
  25                 ".popsection \n\t"
  26                 : :  "i" (&((char *)key)[branch]) : : l_yes);
  27
  28        return false;
  29l_yes:
  30        return true;
  31}
  32
  33static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
  34{
  35        asm_volatile_goto("1:\n\t"
  36                 "b %l[l_yes] # arch_static_branch_jump\n\t"
  37                 ".pushsection __jump_table,  \"aw\"\n\t"
  38                 ".long 1b - ., %l[l_yes] - .\n\t"
  39                 JUMP_ENTRY_TYPE "%c0 - .\n\t"
  40                 ".popsection \n\t"
  41                 : :  "i" (&((char *)key)[branch]) : : l_yes);
  42
  43        return false;
  44l_yes:
  45        return true;
  46}
  47
  48#else
  49#define ARCH_STATIC_BRANCH(LABEL, KEY)          \
  501098:   nop;                                    \
  51        .pushsection __jump_table, "aw";        \
  52        .long 1098b - ., LABEL - .;             \
  53        FTR_ENTRY_LONG KEY - .;                 \
  54        .popsection
  55#endif
  56
  57#endif /* _ASM_POWERPC_JUMP_LABEL_H */
  58