Re: [PATCH V2 09/14] LoongArch: Adjust system call for 32BIT/64BIT

[WANG Xuerui]

On 11/18/25 19:27, Huacai Chen wrote:
> Adjust system call for both 32BIT and 64BIT, including: add the uapi
> unistd_{32,64}.h and syscall_table_{32,64}.h inclusion, add sys_mmap2()
> definition, change the system call entry routines, etc.
>
> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
> ---
>   arch/loongarch/include/asm/Kbuild        |  1 +
>   arch/loongarch/include/uapi/asm/Kbuild   |  1 +
>   arch/loongarch/include/uapi/asm/unistd.h |  6 ++++++
>   arch/loongarch/kernel/Makefile.syscalls  |  1 +
>   arch/loongarch/kernel/entry.S            | 22 +++++++++++-----------
>   arch/loongarch/kernel/syscall.c          | 13 +++++++++++++
>   6 files changed, 33 insertions(+), 11 deletions(-)
>
> [snip]
> diff --git a/arch/loongarch/kernel/syscall.c b/arch/loongarch/kernel/syscall.c
> index ab94eb5ce039..1249d82c1cd0 100644
> --- a/arch/loongarch/kernel/syscall.c
> +++ b/arch/loongarch/kernel/syscall.c
> @@ -34,9 +34,22 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, unsigned long,
>   	return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
>   }
>   
> +SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len, unsigned long,
> +		 prot, unsigned long, flags, unsigned long, fd, unsigned long, offset)
> +{
> +	if (offset & (~PAGE_MASK >> 12))
> +		return -EINVAL;
> +
> +	return ksys_mmap_pgoff(addr, len, prot, flags, fd, offset >> (PAGE_SHIFT - 12));
> +}
> +

Why not guard this with #ifdef CONFIG_32BIT?

>   void *sys_call_table[__NR_syscalls] = {
>   	[0 ... __NR_syscalls - 1] = sys_ni_syscall,
> +#ifdef CONFIG_32BIT
> +#include <asm/syscall_table_32.h>
> +#else
>   #include <asm/syscall_table_64.h>
> +#endif
>   };
>   
>   typedef long (*sys_call_fn)(unsigned long, unsigned long,

--
WANG "xen0n" Xuerui

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