1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_JUMP_LABEL_H 3 #define _ASM_X86_JUMP_LABEL_H 4 5 #define HAVE_JUMP_LABEL_BATCH 6 7 #include <asm/asm.h> 8 #include <asm/nops.h> 9 10 #ifndef __ASSEMBLY__ 11 12 #include <linux/stringify.h> 13 #include <linux/types.h> 14 15 #define JUMP_TABLE_ENTRY \ 16 ".pushsection __jump_table, \"aw\" \n\t" \ 17 _ASM_ALIGN "\n\t" \ 18 ".long 1b - . \n\t" \ 19 ".long %l[l_yes] - . \n\t" \ 20 _ASM_PTR "%c0 + %c1 - .\n\t" \ 21 ".popsection \n\t" 22 23 #ifdef CONFIG_STACK_VALIDATION 24 25 static __always_inline bool arch_static_branch(struct static_key *key, bool branch) 26 { 27 asm_volatile_goto("1:" 28 "jmp %l[l_yes] # objtool NOPs this \n\t" 29 JUMP_TABLE_ENTRY 30 : : "i" (key), "i" (2 | branch) : : l_yes); 31 32 return false; 33 l_yes: 34 return true; 35 } 36 37 #else 38 39 static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) 40 { 41 asm_volatile_goto("1:" 42 ".byte " __stringify(BYTES_NOP5) "\n\t" 43 JUMP_TABLE_ENTRY 44 : : "i" (key), "i" (branch) : : l_yes); 45 46 return false; 47 l_yes: 48 return true; 49 } 50 51 #endif /* STACK_VALIDATION */ 52 53 static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) 54 { 55 asm_volatile_goto("1:" 56 "jmp %l[l_yes]\n\t" 57 JUMP_TABLE_ENTRY 58 : : "i" (key), "i" (branch) : : l_yes); 59 60 return false; 61 l_yes: 62 return true; 63 } 64 65 extern int arch_jump_entry_size(struct jump_entry *entry); 66 67 #endif /* __ASSEMBLY__ */ 68 69 #endif 70