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Date:   Thu, 25 Aug 2022 12:56:00 +0200
From:   Andrew Jones <ajones@ventanamicro.com>
To:     Tong Tiangen <tongtiangen@huawei.com>
Cc:     Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Palmer Dabbelt <palmer@rivosinc.com>,
        Albert Ou <aou@eecs.berkeley.edu>, Conor.Dooley@microchip.com,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        wangkefeng.wang@huawei.com, Guohanjun <guohanjun@huawei.com>
Subject: Re: [PATCH -next v2 1/2] riscv: uaccess: rename
 __get/put_user_nocheck to __get/put_mem_nocheck
Message-ID: <20220825105600.ezueddmwehob42rf@kamzik>
References: <20220815032025.2685516-1-tongtiangen@huawei.com>
 <20220815032025.2685516-2-tongtiangen@huawei.com>
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On Mon, Aug 15, 2022 at 03:20:24AM +0000, Tong Tiangen wrote:
> Current, The helpers __get/put_user_nocheck() is used by get/put_user() and
> __get/put_kernel_nofault(), which is not always uaccess, so the name with
> *user* is not appropriate.
> 
> Also rename xxx_user_xxx to xxx_mem_xx  on the call path of
> __get/put_user_nocheck()
> 
> Only refactor code without any functional changes.
> 
> Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
> ---
>  arch/riscv/include/asm/uaccess.h | 48 ++++++++++++++++----------------
>  1 file changed, 24 insertions(+), 24 deletions(-)
> 
> diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
> index 855450bed9f5..1370da055b44 100644
> --- a/arch/riscv/include/asm/uaccess.h
> +++ b/arch/riscv/include/asm/uaccess.h
> @@ -50,7 +50,7 @@
>   * call.
>   */
>  
> -#define __get_user_asm(insn, x, ptr, err)			\
> +#define __get_mem_asm(insn, x, ptr, err)			\
>  do {								\
>  	__typeof__(x) __x;					\
>  	__asm__ __volatile__ (					\
> @@ -64,12 +64,12 @@ do {								\
>  } while (0)
>  
>  #ifdef CONFIG_64BIT
> -#define __get_user_8(x, ptr, err) \
> -	__get_user_asm("ld", x, ptr, err)
> +#define __get_mem_8(x, ptr, err) \
> +	__get_mem_asm("ld", x, ptr, err)
>  #else /* !CONFIG_64BIT */
> -#define __get_user_8(x, ptr, err)				\
> +#define __get_mem_8(x, ptr, err)				\
>  do {								\
> -	u32 __user *__ptr = (u32 __user *)(ptr);		\
> +	u32 *__ptr = (u32 *)(ptr);				\

Doesn't casting away __user reduce sparse's utility?

>  	u32 __lo, __hi;						\
>  	__asm__ __volatile__ (					\
>  		"1:\n"						\
> @@ -88,20 +88,20 @@ do {								\
>  } while (0)
>  #endif /* CONFIG_64BIT */
>  
> -#define __get_user_nocheck(x, __gu_ptr, __gu_err)		\
> +#define __get_mem_nocheck(x, __gu_ptr, __gu_err)		\

The patch replaces all get/put_user instances with get/put_mem,
but what about 'gu' and 'pu' instances (which are presumably short
for get/put_user)?

Thanks,
drew