Re: [PATCH v3 1/2] linux-user: refactor ipc syscall

[Laurent Vivier]

Le 26/06/2020 à 14:46, Matus Kysel a écrit :
> Refactoring ipc syscall for s390x and SPARC, so it matches glibc 
> implementation
> 
> Signed-off-by: Matus Kysel <mkysel@tachyum.com>
> ---
>  linux-user/syscall.c | 26 +++++++++++++++++++++++++-
>  1 file changed, 25 insertions(+), 1 deletion(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 97de9fb5c9..990412733b 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -814,9 +814,14 @@ safe_syscall4(int, clock_nanosleep, const clockid_t, 
> clock, int, flags,
>                const struct timespec *, req, struct timespec *, rem)
>  #endif
>  #ifdef __NR_ipc
> +#ifdef __s390x__
> +safe_syscall5(int, ipc, int, call, long, first, long, second, long, third,
> +              void *, ptr)
> +#else
>  safe_syscall6(int, ipc, int, call, long, first, long, second, long, third,
>                void *, ptr, long, fifth)
>  #endif
> +#endif
>  #ifdef __NR_msgsnd
>  safe_syscall4(int, msgsnd, int, msgid, const void *, msgp, size_t, sz,
>                int, flags)
> @@ -4053,8 +4058,13 @@ static inline abi_long do_msgsnd(int msqid, abi_long 
> msgp,
>  #endif
>  #ifdef __NR_ipc
>      if (ret == -TARGET_ENOSYS) {
> +#ifdef __s390x__
> +        ret = get_errno(safe_ipc(IPCOP_msgsnd, msqid, msgsz, msgflg,
> +                                 host_mb));
> +#else
>          ret = get_errno(safe_ipc(IPCOP_msgsnd, msqid, msgsz, msgflg,
>                                   host_mb, 0));
> +#endif
>      }
>  #endif
>      g_free(host_mb);
> @@ -4063,6 +4073,20 @@ static inline abi_long do_msgsnd(int msqid, abi_long 
> msgp,
>      return ret;
>  }
>  
> +#ifdef __NR_ipc
> +#if defined(__sparc__)
> +/* SPARC for msgrcv it does not use the kludge on final 2 arguments.  */
> +#define MSGRCV_ARGS(__msgp, __msgtyp) __msgp, __msgtyp
> +#elif defined(__s390x__)
> +/* The s390 sys_ipc variant has only five parameters.  */
> +#define MSGRCV_ARGS(__msgp, __msgtyp) \
> +    ((long int[]){(long int)__msgp, __msgtyp})
> +#else
> +#define MSGRCV_ARGS(__msgp, __msgtyp) \
> +    ((long int[]){(long int)__msgp, __msgtyp}), 0
> +#endif
> +#endif
> +
>  static inline abi_long do_msgrcv(int msqid, abi_long msgp,
>                                   ssize_t msgsz, abi_long msgtyp,
>                                   int msgflg)
> @@ -4091,7 +4115,7 @@ static inline abi_long do_msgrcv(int msqid, abi_long 
> msgp,
>  #ifdef __NR_ipc
>      if (ret == -TARGET_ENOSYS) {
>          ret = get_errno(safe_ipc(IPCOP_CALL(1, IPCOP_msgrcv), msqid, msgsz,
> -                        msgflg, host_mb, msgtyp));
> +                        msgflg, MSGRCV_ARGS(host_mb, msgtyp)));
>      }
>  #endif
>  
> 

This patch breaks build because there is safe_ipc() that is not updated
to use only 5 arguments with s390x. This is updated in the next patch so
the build in the end works, but it breaks bisect so you should fix that.

Otherwise:

Reviewed-by: Laurent Vivier <laurent@vivier.eu>

Thanks,
Laurent