Re: [PATCH 2/2] linux-user: Add support for 'utimensat_time64()' and 'semtimedop_time64()'

[Laurent Vivier <laurent@vivier.eu>]

Le 12/08/2020 à 15:57, Filip Bozuta a écrit :
> This patch introduces functionality for following time64 syscalls:
> 
> *utimensat_time64()
> 
>     int utimensat(int dirfd, const char *pathname,
>                   const struct timespec times[2], int flags);
>     -- change file timestamps with nanosecond precision --
>     man page: https://man7.org/linux/man-pages/man2/utimensat.2.html
> 
> *semtimedop_time64()
> 
>     int semtimedop(int semid, struct sembuf *sops, size_t nsops,
>                    const struct timespec *timeout);
>     -- System V semaphore operations --
>     man page: https://www.man7.org/linux/man-pages/man2/semtimedop.2.html
> 
> Implementation notes:
> 
>    Syscall 'utimensat_time64()' is implemented in similar way as its
>    regular variants only difference being that time64 converting function
>    is used to convert values of 'struct timespec' between host and target
>    ('target_to_host_timespec64()').
> 
>    For syscall 'semtimedop_time64()' and additional argument is added
>    in function 'do_semtimedop()' through which the aproppriate 'struct timespec'
>    converting function is called (0 for regular target_to_host_timespec()
>    and anything else for target_to_host_timespec64()). For 'do_ipc()' an
>    check was added as that additional argument: 'TARGET_ABI_BITS == 64'.
> 
> Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
> ---
>  linux-user/syscall.c | 55 ++++++++++++++++++++++++++++++++++++--------
>  1 file changed, 46 insertions(+), 9 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 8f63a46f58..44a13c5ec2 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -1253,7 +1253,8 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
>  #endif
>  
>  #if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64) || \
> -    defined(TARGET_NR_pselect6_time64) || defined(TARGET_NR_ppoll_time64)
> +    defined(TARGET_NR_pselect6_time64) || defined(TARGET_NR_ppoll_time64) || \
> +    defined(TARGET_NR_utimensat_time64) || defined(TARGET_NR_semtimedop_time64)
>  static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
>                                                   abi_ulong target_addr)
>  {
> @@ -3886,7 +3887,7 @@ static inline abi_long target_to_host_sembuf(struct sembuf *host_sembuf,
>  }
>  
>  #if defined(TARGET_NR_ipc) || defined(TARGET_NR_semop) || \
> -    defined(TARGET_NR_semtimedop)
> +    defined(TARGET_NR_semtimedop) || defined(TARGET_NR_semtimedop_time64)
>  
>  /*
>   * This macro is required to handle the s390 variants, which passes the
> @@ -3903,7 +3904,7 @@ static inline abi_long target_to_host_sembuf(struct sembuf *host_sembuf,
>  static inline abi_long do_semtimedop(int semid,
>                                       abi_long ptr,
>                                       unsigned nsops,
> -                                     abi_long timeout)
> +                                     abi_long timeout, int time64)

"bool time64" would be cleaner

>  {
>      struct sembuf sops[nsops];
>      struct timespec ts, *pts = NULL;
> @@ -3911,7 +3912,10 @@ static inline abi_long do_semtimedop(int semid,
>  
>      if (timeout) {
>          pts = &ts;
> -        if (target_to_host_timespec(pts, timeout)) {
> +        if (!time64 && target_to_host_timespec(pts, timeout)) {
> +            return -TARGET_EFAULT;
> +        }
> +        if (time64 && target_to_host_timespec64(pts, timeout)) {
>              return -TARGET_EFAULT;
>          }

why not:

    if (time64) {
        if (target_to_host_timespec64(pts, timeout)) {
            return -TARGET_EFAULT;
        }
    } else {
        if (target_to_host_timespec(pts, timeout)) {
              return -TARGET_EFAULT;
        }
    }

I think it's clearer.

With that fixed:

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