1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_JUMP_LABEL_H 3 #define _ASM_X86_JUMP_LABEL_H 4 5 #define JUMP_LABEL_NOP_SIZE 5 6 7 #ifdef CONFIG_X86_64 8 # define STATIC_KEY_INIT_NOP P6_NOP5_ATOMIC 9 #else 10 # define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC 11 #endif 12 13 #include <asm/asm.h> 14 #include <asm/nops.h> 15 16 #ifndef __ASSEMBLY__ 17 18 #include <linux/stringify.h> 19 #include <linux/types.h> 20 21 static __always_inline bool arch_static_branch(struct static_key *key, bool branch) 22 { 23 asm_volatile_goto("STATIC_BRANCH_NOP l_yes=\"%l[l_yes]\" key=\"%c0\" " 24 "branch=\"%c1\"" 25 : : "i" (key), "i" (branch) : : l_yes); 26 return false; 27 l_yes: 28 return true; 29 } 30 31 static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch) 32 { 33 asm_volatile_goto("STATIC_BRANCH_JMP l_yes=\"%l[l_yes]\" key=\"%c0\" " 34 "branch=\"%c1\"" 35 : : "i" (key), "i" (branch) : : l_yes); 36 37 return false; 38 l_yes: 39 return true; 40 } 41 42 #else /* __ASSEMBLY__ */ 43 44 .macro STATIC_BRANCH_NOP l_yes:req key:req branch:req 45 .Lstatic_branch_nop_\@: 46 .byte STATIC_KEY_INIT_NOP 47 .Lstatic_branch_no_after_\@: 48 .pushsection __jump_table, "aw" 49 _ASM_ALIGN 50 .long .Lstatic_branch_nop_\@ - ., \l_yes - . 51 _ASM_PTR \key + \branch - . 52 .popsection 53 .endm 54 55 .macro STATIC_BRANCH_JMP l_yes:req key:req branch:req 56 .Lstatic_branch_jmp_\@: 57 .byte 0xe9 58 .long \l_yes - .Lstatic_branch_jmp_after_\@ 59 .Lstatic_branch_jmp_after_\@: 60 .pushsection __jump_table, "aw" 61 _ASM_ALIGN 62 .long .Lstatic_branch_jmp_\@ - ., \l_yes - . 63 _ASM_PTR \key + \branch - . 64 .popsection 65 .endm 66 67 #endif /* __ASSEMBLY__ */ 68 69 #endif 70