arch/powerpc/include/asm/jump_label.h

   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
  18 static __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                  JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
  24                  ".popsection \n\t"
  25                  : :  "i" (&((char *)key)[branch]) : : l_yes);
  26
  27         return false;
  28 l_yes:
  29         return true;
  30 }
  31
  32 static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
  33 {
  34         asm_volatile_goto("1:\n\t"
  35                  "b %l[l_yes] # arch_static_branch_jump\n\t"
  36                  ".pushsection __jump_table,  \"aw\"\n\t"
  37                  JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
  38                  ".popsection \n\t"
  39                  : :  "i" (&((char *)key)[branch]) : : l_yes);
  40
  41         return false;
  42 l_yes:
  43         return true;
  44 }
  45
  46 #ifdef CONFIG_PPC64
  47 typedef u64 jump_label_t;
  48 #else
  49 typedef u32 jump_label_t;
  50 #endif
  51
  52 struct jump_entry {
  53         jump_label_t code;
  54         jump_label_t target;
  55         jump_label_t key;
  56 };
  57
  58 #else
  59 #define ARCH_STATIC_BRANCH(LABEL, KEY)          \
  60 1098:   nop;                                    \
  61         .pushsection __jump_table, "aw";        \
  62         FTR_ENTRY_LONG 1098b, LABEL, KEY;       \
  63         .popsection
  64 #endif
  65
  66 #endif /* _ASM_POWERPC_JUMP_LABEL_H */