[PATCH v4 22/22] klp-build: Add arm64 syscall patching macro

[Josh Poimboeuf <jpoimboe@kernel.org>]

Add arm64 support for KLP_SYSCALL_DEFINEx(), mirroring the arm64
__SYSCALL_DEFINEx() pattern from arch/arm64/include/asm/syscall_wrapper.h.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
 include/linux/livepatch_helpers.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/include/linux/livepatch_helpers.h b/include/linux/livepatch_helpers.h
index 99d68d0773fa8..fe02c7b2f769e 100644
--- a/include/linux/livepatch_helpers.h
+++ b/include/linux/livepatch_helpers.h
@@ -72,6 +72,26 @@
 	}								\
 	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
 
+#elif defined(CONFIG_ARM64)
+
+#define __KLP_SYSCALL_DEFINEx(x, name, ...)				\
+	static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__));	\
+	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
+	asmlinkage long __arm64_sys##name(const struct pt_regs *regs);	\
+	ALLOW_ERROR_INJECTION(__arm64_sys##name, ERRNO);		\
+	asmlinkage long __arm64_sys##name(const struct pt_regs *regs)	\
+	{								\
+		return __se_sys##name(SC_ARM64_REGS_TO_ARGS(x,__VA_ARGS__));\
+	}								\
+	static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))	\
+	{								\
+		long ret = __klp_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
+		__MAP(x,__SC_TEST,__VA_ARGS__);				\
+		__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__));	\
+		return ret;						\
+	}								\
+	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
+
 #endif
 
 #endif /* _LINUX_LIVEPATCH_HELPERS_H */
-- 
2.54.0