[PATCH 01/10] arm64: mm: Introduce a C wrapper for by-level TLB invalidation helpers

[Will Deacon]

In preparation for reducing our reliance on complex preprocessor macros
for TLB invalidation routines, introduce a new C wrapper for by-level
TLB invalidation helpers which can be used instead of the __tlbi() macro
and can additionally be called from C code.

Signed-off-by: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/tlbflush.h | 33 ++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index aa9efee17277..1c7548ec6cb7 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -88,6 +88,16 @@ static inline unsigned long get_trans_granule(void)
 	}
 }
 
+enum tlbi_op {
+	vae1is,
+	vae2is,
+	vale1is,
+	vale2is,
+	vaale1is,
+	ipas2e1,
+	ipas2e1is,
+};
+
 /*
  * Level-based TLBI operations.
  *
@@ -105,6 +115,27 @@ static inline unsigned long get_trans_granule(void)
 
 #define TLBI_TTL_UNKNOWN	INT_MAX
 
+#define __GEN_TLBI_OP_CASE(op)						\
+	case op:							\
+		__tlbi(op, arg);					\
+		break
+
+static __always_inline void __tlbi_level_op(const enum tlbi_op op, u64 arg)
+{
+	switch (op) {
+	__GEN_TLBI_OP_CASE(vae1is);
+	__GEN_TLBI_OP_CASE(vae2is);
+	__GEN_TLBI_OP_CASE(vale1is);
+	__GEN_TLBI_OP_CASE(vale2is);
+	__GEN_TLBI_OP_CASE(vaale1is);
+	__GEN_TLBI_OP_CASE(ipas2e1);
+	__GEN_TLBI_OP_CASE(ipas2e1is);
+	default:
+		BUILD_BUG();
+	}
+}
+#undef __GEN_TLBI_OP_CASE
+
 #define __tlbi_level(op, addr, level) do {				\
 	u64 arg = addr;							\
 									\
@@ -116,7 +147,7 @@ static inline unsigned long get_trans_granule(void)
 		arg |= FIELD_PREP(TLBI_TTL_MASK, ttl);			\
 	}								\
 									\
-	__tlbi(op, arg);						\
+	__tlbi_level_op(op, arg);					\
 } while(0)
 
 #define __tlbi_user_level(op, arg, level) do {				\
-- 
2.50.0.727.gbf7dc18ff4-goog