1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2023 Loongson Technology Corporation Limited 4 * 5 * Based on arch/arm64/include/asm/jump_label.h 6 */ 7 #ifndef __ASM_JUMP_LABEL_H 8 #define __ASM_JUMP_LABEL_H 9 10 #ifndef __ASSEMBLER__ 11 12 #include <linux/types.h> 13 #include <linux/stringify.h> 14 #include <asm/asm.h> 15 16 #define JUMP_LABEL_NOP_SIZE 4 17 18 #ifdef CONFIG_32BIT 19 #define JUMP_LABEL_TYPE ".long " 20 #else 21 #define JUMP_LABEL_TYPE ".quad " 22 #endif 23 24 /* This macro is also expanded on the Rust side. */ 25 #define JUMP_TABLE_ENTRY(key, label) \ 26 ".pushsection __jump_table, \"aw\" \n\t" \ 27 ".align " __stringify(PTRLOG) " \n\t" \ 28 ".long 1b - ., " label " - . \n\t" \ 29 JUMP_LABEL_TYPE key " - . \n\t" \ 30 ".popsection \n\t" 31 32 #define ARCH_STATIC_BRANCH_ASM(key, label) \ 33 "1: nop \n\t" \ 34 JUMP_TABLE_ENTRY(key, label) 35 36 static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) 37 { 38 asm goto( 39 ARCH_STATIC_BRANCH_ASM("%0", "%l[l_yes]") 40 : : "i"(&((char *)key)[branch]) : : l_yes); 41 42 return false; 43 44 l_yes: 45 return true; 46 } 47 48 static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) 49 { 50 asm goto( 51 "1: b %l[l_yes] \n\t" 52 JUMP_TABLE_ENTRY("%0", "%l[l_yes]") 53 : : "i"(&((char *)key)[branch]) : : l_yes); 54 55 return false; 56 57 l_yes: 58 return true; 59 } 60 61 #endif /* __ASSEMBLER__ */ 62 #endif /* __ASM_JUMP_LABEL_H */ 63