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-rw-r--r--arch/riscv/include/asm/extable.h52
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/extable.h b/arch/riscv/include/asm/extable.h
new file mode 100644
index 0000000000..3eb5c1f7bf
--- /dev/null
+++ b/arch/riscv/include/asm/extable.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_RISCV_EXTABLE_H
+#define _ASM_RISCV_EXTABLE_H
+
+/*
+ * The exception table consists of pairs of relative offsets: the first
+ * is the relative offset to an instruction that is allowed to fault,
+ * and the second is the relative offset at which the program should
+ * continue. No registers are modified, so it is entirely up to the
+ * continuation code to figure out what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path. This means when everything is well,
+ * we don't even have to jump over them. Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry {
+ int insn, fixup;
+ short type, data;
+};
+
+#define ARCH_HAS_RELATIVE_EXTABLE
+
+#define swap_ex_entry_fixup(a, b, tmp, delta) \
+do { \
+ (a)->fixup = (b)->fixup + (delta); \
+ (b)->fixup = (tmp).fixup - (delta); \
+ (a)->type = (b)->type; \
+ (b)->type = (tmp).type; \
+ (a)->data = (b)->data; \
+ (b)->data = (tmp).data; \
+} while (0)
+
+#ifdef CONFIG_MMU
+bool fixup_exception(struct pt_regs *regs);
+#else
+static inline bool fixup_exception(struct pt_regs *regs) { return false; }
+#endif
+
+#if defined(CONFIG_BPF_JIT) && defined(CONFIG_ARCH_RV64I)
+bool ex_handler_bpf(const struct exception_table_entry *ex, struct pt_regs *regs);
+#else
+static inline bool
+ex_handler_bpf(const struct exception_table_entry *ex,
+ struct pt_regs *regs)
+{
+ return false;
+}
+#endif
+
+#endif