1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_EXTABLE_H 3 #define __ASM_EXTABLE_H 4 5 /* 6 * The exception table consists of pairs of relative offsets: the first 7 * is the relative offset to an instruction that is allowed to fault, 8 * and the second is the relative offset at which the program should 9 * continue. No registers are modified, so it is entirely up to the 10 * continuation code to figure out what to do. 11 * 12 * All the routines below use bits of fixup code that are out of line 13 * with the main instruction path. This means when everything is well, 14 * we don't even have to jump over them. Further, they do not intrude 15 * on our cache or tlb entries. 16 */ 17 18 struct exception_table_entry 19 { 20 int insn, fixup; 21 }; 22 23 #define ARCH_HAS_RELATIVE_EXTABLE 24 25 static inline bool in_bpf_jit(struct pt_regs *regs) 26 { 27 if (!IS_ENABLED(CONFIG_BPF_JIT)) 28 return false; 29 30 return regs->pc >= BPF_JIT_REGION_START && 31 regs->pc < BPF_JIT_REGION_END; 32 } 33 34 #ifdef CONFIG_BPF_JIT 35 int arm64_bpf_fixup_exception(const struct exception_table_entry *ex, 36 struct pt_regs *regs); 37 #else /* !CONFIG_BPF_JIT */ 38 static inline 39 int arm64_bpf_fixup_exception(const struct exception_table_entry *ex, 40 struct pt_regs *regs) 41 { 42 return 0; 43 } 44 #endif /* !CONFIG_BPF_JIT */ 45 46 extern int fixup_exception(struct pt_regs *regs); 47 #endif 48