[PATCH 08/12] riscv: extable: consolidate definitions

From: Jisheng Zhang
Date: Thu Nov 18 2021 - 06:36:54 EST


From: Jisheng Zhang <jszhang@xxxxxxxxxx>

This is a riscv port of commit 819771cc2892 ("arm64: extable:
consolidate definitions").

In subsequent patches we'll alter the structure and usage of struct
exception_table_entry.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
arch/riscv/include/asm/asm-extable.h | 33 ++++++++++++++++++++++++++++
arch/riscv/include/asm/futex.h | 1 +
arch/riscv/include/asm/uaccess.h | 7 +-----
arch/riscv/lib/uaccess.S | 6 ++---
4 files changed, 37 insertions(+), 10 deletions(-)
create mode 100644 arch/riscv/include/asm/asm-extable.h

diff --git a/arch/riscv/include/asm/asm-extable.h b/arch/riscv/include/asm/asm-extable.h
new file mode 100644
index 000000000000..b790c02dbdda
--- /dev/null
+++ b/arch/riscv/include/asm/asm-extable.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_ASM_EXTABLE_H
+#define __ASM_ASM_EXTABLE_H
+
+#ifdef __ASSEMBLY__
+
+#define __ASM_EXTABLE_RAW(insn, fixup) \
+ .pushsection __ex_table, "a"; \
+ .balign 4; \
+ .long ((insn) - .); \
+ .long ((fixup) - .); \
+ .popsection;
+
+ .macro _asm_extable, insn, fixup
+ __ASM_EXTABLE_RAW(\insn, \fixup)
+ .endm
+
+#else /* __ASSEMBLY__ */
+
+#include <linux/stringify.h>
+
+#define __ASM_EXTABLE_RAW(insn, fixup) \
+ ".pushsection __ex_table, \"a\"\n" \
+ ".balign 4\n" \
+ ".long ((" insn ") - .)\n" \
+ ".long ((" fixup ") - .)\n" \
+ ".popsection\n"
+
+#define _ASM_EXTABLE(insn, fixup) __ASM_EXTABLE_RAW(#insn, #fixup)
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_ASM_EXTABLE_H */
diff --git a/arch/riscv/include/asm/futex.h b/arch/riscv/include/asm/futex.h
index 3191574e135c..2e15e8e89502 100644
--- a/arch/riscv/include/asm/futex.h
+++ b/arch/riscv/include/asm/futex.h
@@ -11,6 +11,7 @@
#include <linux/uaccess.h>
#include <linux/errno.h>
#include <asm/asm.h>
+#include <asm/asm-extable.h>

/* We don't even really need the extable code, but for now keep it simple */
#ifndef CONFIG_MMU
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index 0f2c5b9d2e8f..40e6099af488 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -8,14 +8,9 @@
#ifndef _ASM_RISCV_UACCESS_H
#define _ASM_RISCV_UACCESS_H

+#include <asm/asm-extable.h>
#include <asm/pgtable.h> /* for TASK_SIZE */

-#define _ASM_EXTABLE(from, to) \
- " .pushsection __ex_table, \"a\"\n" \
- " .balign 4\n" \
- " .long (" #from " - .), (" #to " - .)\n" \
- " .popsection\n"
-
/*
* User space memory access functions
*/
diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index 047f517ac780..8c475f4da308 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -1,15 +1,13 @@
#include <linux/linkage.h>
#include <asm-generic/export.h>
#include <asm/asm.h>
+#include <asm/asm-extable.h>
#include <asm/csr.h>

.macro fixup op reg addr lbl
100:
\op \reg, \addr
- .section __ex_table,"a"
- .balign 4
- .long (100b - .), (\lbl - .)
- .previous
+ _asm_extable 100b, \lbl
.endm

ENTRY(__asm_copy_to_user)
--
2.33.0