[PATCH -next v2 2/2] riscv: extable: add new extable type EX_TYPE_KACCESS_ERR_ZERO support
From: Tong Tiangen
Date: Sun Aug 14 2022 - 23:21:08 EST
Currently, The extable type EX_TYPE_UACCESS_ERR_ZERO is used by
__get/put_kernel_nofault(), but those helpers are not uaccess type, so we
add a new extable type EX_TYPE_KACCESS_ERR_ZERO which can be used by
__get/put_kernel_no_fault().
Only refactor code without any functional changes.
Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
---
arch/riscv/include/asm/asm-extable.h | 12 ++
arch/riscv/include/asm/uaccess.h | 160 +++++++++++++--------------
arch/riscv/mm/extable.c | 1 +
3 files changed, 93 insertions(+), 80 deletions(-)
diff --git a/arch/riscv/include/asm/asm-extable.h b/arch/riscv/include/asm/asm-extable.h
index 14be0673f5b5..73c70098a9c8 100644
--- a/arch/riscv/include/asm/asm-extable.h
+++ b/arch/riscv/include/asm/asm-extable.h
@@ -6,6 +6,7 @@
#define EX_TYPE_FIXUP 1
#define EX_TYPE_BPF 2
#define EX_TYPE_UACCESS_ERR_ZERO 3
+#define EX_TYPE_KACCESS_ERR_ZERO 4
#ifdef __ASSEMBLY__
@@ -57,9 +58,20 @@
EX_DATA_REG(ZERO, zero) \
")")
+#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), \
+ "(" \
+ EX_DATA_REG(ERR, err) " | " \
+ EX_DATA_REG(ZERO, zero) \
+ ")")
+
#define _ASM_EXTABLE_UACCESS_ERR(insn, fixup, err) \
_ASM_EXTABLE_UACCESS_ERR_ZERO(insn, fixup, err, zero)
+#define _ASM_EXTABLE_KACCESS_ERR(insn, fixup, err) \
+ _ASM_EXTABLE_KACCESS_ERR_ZERO(insn, fixup, err, zero)
#endif /* __ASSEMBLY__ */
#endif /* __ASM_ASM_EXTABLE_H */
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
index 1370da055b44..a79af147636e 100644
--- a/arch/riscv/include/asm/uaccess.h
+++ b/arch/riscv/include/asm/uaccess.h
@@ -50,62 +50,62 @@
* call.
*/
-#define __get_mem_asm(insn, x, ptr, err) \
-do { \
- __typeof__(x) __x; \
- __asm__ __volatile__ ( \
- "1:\n" \
- " " insn " %1, %2\n" \
- "2:\n" \
- _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 2b, %0, %1) \
- : "+r" (err), "=&r" (__x) \
- : "m" (*(ptr))); \
- (x) = __x; \
+#define __get_mem_asm(insn, x, ptr, err, type) \
+do { \
+ __typeof__(x) __x; \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " " insn " %1, %2\n" \
+ "2:\n" \
+ _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(1b, 2b, %0, %1) \
+ : "+r" (err), "=&r" (__x) \
+ : "m" (*(ptr))); \
+ (x) = __x; \
} while (0)
#ifdef CONFIG_64BIT
-#define __get_mem_8(x, ptr, err) \
- __get_mem_asm("ld", x, ptr, err)
+#define __get_mem_8(x, ptr, err, type) \
+ __get_mem_asm("ld", x, ptr, err, type)
#else /* !CONFIG_64BIT */
-#define __get_mem_8(x, ptr, err) \
-do { \
- u32 *__ptr = (u32 *)(ptr); \
- u32 __lo, __hi; \
- __asm__ __volatile__ ( \
- "1:\n" \
- " lw %1, %3\n" \
- "2:\n" \
- " lw %2, %4\n" \
- "3:\n" \
- _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 3b, %0, %1) \
- _ASM_EXTABLE_UACCESS_ERR_ZERO(2b, 3b, %0, %1) \
- : "+r" (err), "=&r" (__lo), "=r" (__hi) \
- : "m" (__ptr[__LSW]), "m" (__ptr[__MSW])); \
- if (err) \
- __hi = 0; \
- (x) = (__typeof__(x))((__typeof__((x)-(x)))( \
- (((u64)__hi << 32) | __lo))); \
+#define __get_mem_8(x, ptr, err, type) \
+do { \
+ u32 *__ptr = (u32 *)(ptr); \
+ u32 __lo, __hi; \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " lw %1, %3\n" \
+ "2:\n" \
+ " lw %2, %4\n" \
+ "3:\n" \
+ _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(1b, 3b, %0, %1) \
+ _ASM_EXTABLE_##type##ACCESS_ERR_ZERO(2b, 3b, %0, %1) \
+ : "+r" (err), "=&r" (__lo), "=r" (__hi) \
+ : "m" (__ptr[__LSW]), "m" (__ptr[__MSW])); \
+ if (err) \
+ __hi = 0; \
+ (x) = (__typeof__(x))((__typeof__((x)-(x)))( \
+ (((u64)__hi << 32) | __lo))); \
} while (0)
#endif /* CONFIG_64BIT */
-#define __get_mem_nocheck(x, __gu_ptr, __gu_err) \
-do { \
- switch (sizeof(*__gu_ptr)) { \
- case 1: \
- __get_mem_asm("lb", (x), __gu_ptr, __gu_err); \
- break; \
- case 2: \
- __get_mem_asm("lh", (x), __gu_ptr, __gu_err); \
- break; \
- case 4: \
- __get_mem_asm("lw", (x), __gu_ptr, __gu_err); \
- break; \
- case 8: \
- __get_mem_8((x), __gu_ptr, __gu_err); \
- break; \
- default: \
- BUILD_BUG(); \
- } \
+#define __get_mem_nocheck(x, __gu_ptr, __gu_err, type) \
+do { \
+ switch (sizeof(*__gu_ptr)) { \
+ case 1: \
+ __get_mem_asm("lb", (x), __gu_ptr, __gu_err, type); \
+ break; \
+ case 2: \
+ __get_mem_asm("lh", (x), __gu_ptr, __gu_err, type); \
+ break; \
+ case 4: \
+ __get_mem_asm("lw", (x), __gu_ptr, __gu_err, type); \
+ break; \
+ case 8: \
+ __get_mem_8((x), __gu_ptr, __gu_err, type); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
} while (0)
/**
@@ -136,7 +136,7 @@ do { \
__chk_user_ptr(__gu_ptr); \
\
__enable_user_access(); \
- __get_mem_nocheck(x, __gu_ptr, __gu_err); \
+ __get_mem_nocheck(x, __gu_ptr, __gu_err, U); \
__disable_user_access(); \
\
__gu_err; \
@@ -163,28 +163,28 @@ do { \
({ \
const __typeof__(*(ptr)) __user *__p = (ptr); \
might_fault(); \
- access_ok(__p, sizeof(*__p)) ? \
+ access_ok(__p, sizeof(*__p)) ? \
__get_user((x), __p) : \
((x) = 0, -EFAULT); \
})
-#define __put_mem_asm(insn, x, ptr, err) \
+#define __put_mem_asm(insn, x, ptr, err, type) \
do { \
__typeof__(*(ptr)) __x = x; \
__asm__ __volatile__ ( \
"1:\n" \
" " insn " %z2, %1\n" \
"2:\n" \
- _ASM_EXTABLE_UACCESS_ERR(1b, 2b, %0) \
+ _ASM_EXTABLE_##type##ACCESS_ERR(1b, 2b, %0) \
: "+r" (err), "=m" (*(ptr)) \
: "rJ" (__x)); \
} while (0)
#ifdef CONFIG_64BIT
-#define __put_mem_8(x, ptr, err) \
- __put_mem_asm("sd", x, ptr, err)
+#define __put_mem_8(x, ptr, err, type) \
+ __put_mem_asm("sd", x, ptr, err, type)
#else /* !CONFIG_64BIT */
-#define __put_mem_8(x, ptr, err) \
+#define __put_mem_8(x, ptr, err, type) \
do { \
u32 *__ptr = (u32 *)(ptr); \
u64 __x = (__typeof__((x)-(x)))(x); \
@@ -194,8 +194,8 @@ do { \
"2:\n" \
" sw %z4, %2\n" \
"3:\n" \
- _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) \
- _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) \
+ _ASM_EXTABLE_##type##ACCESS_ERR(1b, 3b, %0) \
+ _ASM_EXTABLE_##type##ACCESS_ERR(2b, 3b, %0) \
: "+r" (err), \
"=m" (__ptr[__LSW]), \
"=m" (__ptr[__MSW]) \
@@ -203,24 +203,24 @@ do { \
} while (0)
#endif /* CONFIG_64BIT */
-#define __put_mem_nocheck(x, __gu_ptr, __pu_err) \
-do { \
- switch (sizeof(*__gu_ptr)) { \
- case 1: \
- __put_mem_asm("sb", (x), __gu_ptr, __pu_err); \
- break; \
- case 2: \
- __put_mem_asm("sh", (x), __gu_ptr, __pu_err); \
- break; \
- case 4: \
- __put_mem_asm("sw", (x), __gu_ptr, __pu_err); \
- break; \
- case 8: \
- __put_mem_8((x), __gu_ptr, __pu_err); \
- break; \
- default: \
- BUILD_BUG(); \
- } \
+#define __put_mem_nocheck(x, __gu_ptr, __pu_err, type) \
+do { \
+ switch (sizeof(*__gu_ptr)) { \
+ case 1: \
+ __put_mem_asm("sb", (x), __gu_ptr, __pu_err, type); \
+ break; \
+ case 2: \
+ __put_mem_asm("sh", (x), __gu_ptr, __pu_err, type); \
+ break; \
+ case 4: \
+ __put_mem_asm("sw", (x), __gu_ptr, __pu_err, type); \
+ break; \
+ case 8: \
+ __put_mem_8((x), __gu_ptr, __pu_err, type); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
} while (0)
/**
@@ -253,7 +253,7 @@ do { \
__chk_user_ptr(__gu_ptr); \
\
__enable_user_access(); \
- __put_mem_nocheck(__val, __gu_ptr, __pu_err); \
+ __put_mem_nocheck(__val, __gu_ptr, __pu_err, U); \
__disable_user_access(); \
\
__pu_err; \
@@ -279,7 +279,7 @@ do { \
({ \
__typeof__(*(ptr)) __user *__p = (ptr); \
might_fault(); \
- access_ok(__p, sizeof(*__p)) ? \
+ access_ok(__p, sizeof(*__p)) ? \
__put_user((x), __p) : \
-EFAULT; \
})
@@ -321,7 +321,7 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n)
do { \
long __kr_err; \
\
- __get_mem_nocheck(*((type *)(dst)), (type *)(src), __kr_err); \
+ __get_mem_nocheck(*((type *)(dst)), (type *)(src), __kr_err, K);\
if (unlikely(__kr_err)) \
goto err_label; \
} while (0)
@@ -330,7 +330,7 @@ do { \
do { \
long __kr_err; \
\
- __put_mem_nocheck(*((type *)(src)), (type *)(dst), __kr_err); \
+ __put_mem_nocheck(*((type *)(src)), (type *)(dst), __kr_err, K);\
if (unlikely(__kr_err)) \
goto err_label; \
} while (0)
diff --git a/arch/riscv/mm/extable.c b/arch/riscv/mm/extable.c
index 35484d830fd6..a21ad8237189 100644
--- a/arch/riscv/mm/extable.c
+++ b/arch/riscv/mm/extable.c
@@ -64,6 +64,7 @@ bool fixup_exception(struct pt_regs *regs)
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);
}
--
2.25.1