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-rw-r--r--arch/powerpc/include/asm/extable.h44
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diff --git a/arch/powerpc/include/asm/extable.h b/arch/powerpc/include/asm/extable.h
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+++ b/arch/powerpc/include/asm/extable.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ARCH_POWERPC_EXTABLE_H
+#define _ARCH_POWERPC_EXTABLE_H
+
+/*
+ * The exception table consists of pairs of relative addresses: the first is
+ * the address of an instruction that is allowed to fault, and the second is
+ * the address 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.
+ */
+
+#define ARCH_HAS_RELATIVE_EXTABLE
+
+#ifndef __ASSEMBLY__
+
+struct exception_table_entry {
+ int insn;
+ int fixup;
+};
+
+static inline unsigned long extable_fixup(const struct exception_table_entry *x)
+{
+ return (unsigned long)&x->fixup + x->fixup;
+}
+
+#endif
+
+/*
+ * Helper macro for exception table entries
+ */
+#define EX_TABLE(_fault, _target) \
+ stringify_in_c(.section __ex_table,"a";)\
+ stringify_in_c(.balign 4;) \
+ stringify_in_c(.long (_fault) - . ;) \
+ stringify_in_c(.long (_target) - . ;) \
+ stringify_in_c(.previous)
+
+#endif