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-rw-r--r--arch/x86/include/asm/extable.h37
1 files changed, 37 insertions, 0 deletions
diff --git a/arch/x86/include/asm/extable.h b/arch/x86/include/asm/extable.h
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index 000000000..f9c3a5d50
--- /dev/null
+++ b/arch/x86/include/asm/extable.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_EXTABLE_H
+#define _ASM_X86_EXTABLE_H
+/*
+ * The exception table consists of triples of addresses relative to the
+ * exception table entry itself. The first address is of an instruction
+ * that is allowed to fault, the second is the target at which the program
+ * should continue. The third is a handler function to deal with the fault
+ * caused by the instruction in the first field.
+ *
+ * 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, handler;
+};
+struct pt_regs;
+
+#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)->handler = (b)->handler + (delta); \
+ (b)->handler = (tmp).handler - (delta); \
+ } while (0)
+
+extern int fixup_exception(struct pt_regs *regs, int trapnr);
+extern int fixup_bug(struct pt_regs *regs, int trapnr);
+extern bool ex_has_fault_handler(unsigned long ip);
+extern void early_fixup_exception(struct pt_regs *regs, int trapnr);
+
+#endif