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 HAVE_JUMP_LABEL_BATCH 17 18 #define JUMP_LABEL_NOP_SIZE 4 19 20 #ifdef CONFIG_32BIT 21 #define JUMP_LABEL_TYPE ".long " 22 #else 23 #define JUMP_LABEL_TYPE ".quad " 24 #endif 25 26 /* This macro is also expanded on the Rust side. */ 27 #define JUMP_TABLE_ENTRY(key, label) \ 28 ".pushsection __jump_table, \"aw\" \n\t" \ 29 ".align " __stringify(PTRLOG) " \n\t" \ 30 ".long 1b - ., " label " - . \n\t" \ 31 JUMP_LABEL_TYPE key " - . \n\t" \ 32 ".popsection \n\t" 33 34 #define ARCH_STATIC_BRANCH_ASM(key, label) \ 35 "1: nop \n\t" \ 36 JUMP_TABLE_ENTRY(key, label) 37 38 static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) 39 { 40 asm goto( 41 ARCH_STATIC_BRANCH_ASM("%0", "%l[l_yes]") 42 : : "i"(&((char *)key)[branch]) : : l_yes); 43 44 return false; 45 46 l_yes: 47 return true; 48 } 49 50 static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) 51 { 52 asm goto( 53 "1: b %l[l_yes] \n\t" 54 JUMP_TABLE_ENTRY("%0", "%l[l_yes]") 55 : : "i"(&((char *)key)[branch]) : : l_yes); 56 57 return false; 58 59 l_yes: 60 return true; 61 } 62 63 #endif /* __ASSEMBLER__ */ 64 #endif /* __ASM_JUMP_LABEL_H */ 65