[PATCH v2 1/2] riscv: consolidate __ex_table construction

Jisheng Zhang
2021-10-20T14:13:04Z

From: Jisheng Zhang <jszhang@kernel.org>

Consolidate all the __ex_table constuction code with a _ASM_EXTABLE
helper.

There should be no functional change as a result of this patch.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
arch/riscv/include/asm/futex.h | 12 +++-------
arch/riscv/include/asm/uaccess.h | 40 +++++++++++---------------------
2 files changed, 17 insertions(+), 35 deletions(-)

diff --git a/arch/riscv/include/asm/futex.h b/arch/riscv/include/asm/futex.h
index 1b00badb9f87..3191574e135c 100644
--- a/arch/riscv/include/asm/futex.h
+++ b/arch/riscv/include/asm/futex.h
@@ -30,10 +30,7 @@
"3: li %[r],%[e] \n" \
" jump 2b,%[t] \n" \
" .previous \n" \
- " .section __ex_table,\"a\" \n" \
- " .balign " RISCV_SZPTR " \n" \
- " " RISCV_PTR " 1b, 3b \n" \
- " .previous \n" \
+ _ASM_EXTABLE(1b, 3b) \
: [r] "+r" (ret), [ov] "=&r" (oldval), \
[u] "+m" (*uaddr), [t] "=&r" (tmp) \
: [op] "Jr" (oparg), [e] "i" (-EFAULT) \
@@ -103,11 +100,8 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
"4: li %[r],%[e] \n"
" jump 3b,%[t] \n"
" .previous \n"
- " .section __ex_table,\"a\" \n"
- " .balign " RISCV_SZPTR " \n"
- " " RISCV_PTR " 1b, 4b \n"
- " " RISCV_PTR " 2b, 4b \n"
- " .previous \n"
+ _ASM_EXTABLE(1b, 4b) \
+ _ASM_EXTABLE(2b, 4b) \
: [r] "+r" (ret), [v] "=&r" (val), [u] "+m" (*uaddr), [t] "=&r" (tmp)
: [ov] "Jr" (oldval), [nv] "Jr" (newval), [e] "i" (-EFAULT)
: "memory");
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index f314ff44c48d..35802e72ace8 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -10,6 +10,12 @@

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

+#define _ASM_EXTABLE(from, to) \
+ " .pushsection __ex_table, \"a\"\n" \
+ " .balign " RISCV_SZPTR " \n" \
+ " " RISCV_PTR "(" #from "), (" #to ")\n" \
+ " .popsection\n"
+
/*
* User space memory access functions
*/
@@ -93,10 +99,7 @@ do { \
" li %1, 0\n" \
" jump 2b, %2\n" \
" .previous\n" \
- " .section __ex_table,\"a\"\n" \
- " .balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 3b\n" \
- " .previous" \
+ _ASM_EXTABLE(1b, 3b) \
: "+r" (err), "=&r" (__x), "=r" (__tmp) \
: "m" (*(ptr)), "i" (-EFAULT)); \
(x) = __x; \
@@ -125,11 +128,8 @@ do { \
" li %2, 0\n" \
" jump 3b, %3\n" \
" .previous\n" \
- " .section __ex_table,\"a\"\n" \
- " .balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 4b\n" \
- " " RISCV_PTR " 2b, 4b\n" \
- " .previous" \
+ _ASM_EXTABLE(1b, 4b) \
+ _ASM_EXTABLE(2b, 4b) \
: "+r" (err), "=&r" (__lo), "=r" (__hi), \
"=r" (__tmp) \
: "m" (__ptr[__LSW]), "m" (__ptr[__MSW]), \
@@ -233,10 +233,7 @@ do { \
" li %0, %4\n" \
" jump 2b, %1\n" \
" .previous\n" \
- " .section __ex_table,\"a\"\n" \
- " .balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 3b\n" \
- " .previous" \
+ _ASM_EXTABLE(1b, 3b) \
: "+r" (err), "=r" (__tmp), "=m" (*(ptr)) \
: "rJ" (__x), "i" (-EFAULT)); \
} while (0)
@@ -262,11 +259,8 @@ do { \
" li %0, %6\n" \
" jump 3b, %1\n" \
" .previous\n" \
- " .section __ex_table,\"a\"\n" \
- " .balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 4b\n" \
- " " RISCV_PTR " 2b, 4b\n" \
- " .previous" \
+ _ASM_EXTABLE(1b, 4b) \
+ _ASM_EXTABLE(2b, 4b) \
: "+r" (err), "=r" (__tmp), \
"=m" (__ptr[__LSW]), \
"=m" (__ptr[__MSW]) \
@@ -417,10 +411,7 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n)
" li %[err], %[efault]\n" \
" jump 1b, %[rc]\n" \
".previous\n" \
- ".section __ex_table,\"a\"\n" \
- ".balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 2b\n" \
- ".previous\n" \
+ _ASM_EXTABLE(1b, 2b) \
: [ret] "=&r" (__ret), \
[rc] "=&r" (__rc), \
[ptr] "+A" (*__ptr), \
@@ -443,10 +434,7 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n)
" li %[err], %[efault]\n" \
" jump 1b, %[rc]\n" \
".previous\n" \
- ".section __ex_table,\"a\"\n" \
- ".balign " RISCV_SZPTR "\n" \
- " " RISCV_PTR " 1b, 2b\n" \
- ".previous\n" \
+ _ASM_EXTABLE(1b, 2b) \
: [ret] "=&r" (__ret), \
[rc] "=&r" (__rc), \
[ptr] "+A" (*__ptr), \
--
2.33.0