[PATCH v15 3/9] arm64: extable: merge UACCESS_ERR_ZERO and KACCESS_ERR_ZERO into ACCESS_ERR_ZERO

[Ruidong Tian]

EX_TYPE_UACCESS_ERR_ZERO and EX_TYPE_KACCESS_ERR_ZERO have identical
handling in fixup_exception(): both unconditionally invoke
ex_handler_uaccess_err_zero() to set the error register to -EFAULT,
zero the destination register, and branch to the fixup address.

Merge them into a single EX_TYPE_ACCESS_ERR_ZERO to reduce redundancy
and renumber the subsequent types accordingly.

The _ASM_EXTABLE_UACCESS_ERR_ZERO and _ASM_EXTABLE_KACCESS_ERR_ZERO
helper macros are preserved as-is for caller readability, but both now
emit the unified EX_TYPE_ACCESS_ERR_ZERO type.

Signed-off-by: Ruidong Tian <tianruidong@xxxxxxxxxxxxxxxxx>
---
 arch/arm64/include/asm/asm-extable.h | 15 +++++++--------
 arch/arm64/mm/extable.c              |  7 +++----
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/include/asm/asm-extable.h b/arch/arm64/include/asm/asm-extable.h
index d67e2fdd1aee..06b19023939b 100644
--- a/arch/arm64/include/asm/asm-extable.h
+++ b/arch/arm64/include/asm/asm-extable.h
@@ -7,12 +7,11 @@
 
 #define EX_TYPE_NONE			0
 #define EX_TYPE_BPF			1
-#define EX_TYPE_UACCESS_ERR_ZERO	2
-#define EX_TYPE_KACCESS_ERR_ZERO	3
-#define EX_TYPE_UACCESS_CPY		4
-#define EX_TYPE_LOAD_UNALIGNED_ZEROPAD	5
+#define EX_TYPE_ACCESS_ERR_ZERO		2
+#define EX_TYPE_UACCESS_CPY		3
+#define EX_TYPE_LOAD_UNALIGNED_ZEROPAD	4
 
-/* Data fields for EX_TYPE_UACCESS_ERR_ZERO */
+/* Data fields for EX_TYPE_ACCESS_ERR_ZERO */
 #define EX_DATA_REG_ERR_SHIFT	0
 #define EX_DATA_REG_ERR		GENMASK(4, 0)
 #define EX_DATA_REG_ZERO_SHIFT	5
@@ -43,7 +42,7 @@
 
 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)		\
 	__ASM_EXTABLE_RAW(insn, fixup, 					\
-			  EX_TYPE_UACCESS_ERR_ZERO,			\
+			  EX_TYPE_ACCESS_ERR_ZERO,			\
 			  (						\
 			    EX_DATA_REG(ERR, err) |			\
 			    EX_DATA_REG(ZERO, zero)			\
@@ -96,7 +95,7 @@
 #define _ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)		\
 	__DEFINE_ASM_GPR_NUMS						\
 	__ASM_EXTABLE_RAW(#insn, #fixup, 				\
-			  __stringify(EX_TYPE_UACCESS_ERR_ZERO),	\
+			  __stringify(EX_TYPE_ACCESS_ERR_ZERO),	\
 			  "("						\
 			    EX_DATA_REG(ERR, err) " | "			\
 			    EX_DATA_REG(ZERO, zero)			\
@@ -105,7 +104,7 @@
 #define _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, zero)		\
 	__DEFINE_ASM_GPR_NUMS						\
 	__ASM_EXTABLE_RAW(#insn, #fixup, 				\
-			  __stringify(EX_TYPE_KACCESS_ERR_ZERO),	\
+			  __stringify(EX_TYPE_ACCESS_ERR_ZERO),	\
 			  "("						\
 			    EX_DATA_REG(ERR, err) " | "			\
 			    EX_DATA_REG(ZERO, zero)			\
diff --git a/arch/arm64/mm/extable.c b/arch/arm64/mm/extable.c
index 6e0528831cd3..76b18780f1f9 100644
--- a/arch/arm64/mm/extable.c
+++ b/arch/arm64/mm/extable.c
@@ -41,7 +41,7 @@ get_ex_fixup(const struct exception_table_entry *ex)
 	return ((unsigned long)&ex->fixup + ex->fixup);
 }
 
-static bool ex_handler_uaccess_err_zero(const struct exception_table_entry *ex,
+static bool ex_handler_access_err_zero(const struct exception_table_entry *ex,
 					struct pt_regs *regs)
 {
 	int reg_err = FIELD_GET(EX_DATA_REG_ERR, ex->data);
@@ -103,9 +103,8 @@ bool fixup_exception(struct pt_regs *regs, unsigned long esr)
 	switch (ex->type) {
 	case EX_TYPE_BPF:
 		return ex_handler_bpf(ex, regs);
-	case EX_TYPE_UACCESS_ERR_ZERO:
-	case EX_TYPE_KACCESS_ERR_ZERO:
-		return ex_handler_uaccess_err_zero(ex, regs);
+	case EX_TYPE_ACCESS_ERR_ZERO:
+		return ex_handler_access_err_zero(ex, regs);
 	case EX_TYPE_UACCESS_CPY:
 		return ex_handler_uaccess_cpy(ex, regs, esr);
 	case EX_TYPE_LOAD_UNALIGNED_ZEROPAD:
-- 
2.39.3