Re: [PATCH] Use struct for time_value_t and define seconds as long_integer_t.

[Samuel Thibault]

Applied, thanks!

Flavio Cruz, le ven. 16 déc. 2022 21:06:25 -0500, a ecrit:
> On 64 bit kernels, seconds will be 64 bits long and won't suffer from
> the 2038 problem. We also add a new type rpc_time_value_t to handle the
> conversion between 32 bit userland and 64 bit kernel.

Yes, I was thinking that we'd just switch to 64bit time with the 64bit
kernel.

We have the same issue with the device_read/write operations, for which
we'd want to make the offset 64bit.

Samuel

> ---
>  i386/include/mach/i386/machine_types.defs | 16 ++++++++++++--
>  i386/include/mach/i386/vm_types.h         |  8 +++++++
>  include/mach/mach_types.defs              | 13 ++++++++++-
>  include/mach/time_value.h                 | 27 ++++++++++++++++++++++-
>  4 files changed, 60 insertions(+), 4 deletions(-)
> 
> diff --git a/i386/include/mach/i386/machine_types.defs 
> b/i386/include/mach/i386/machine_types.defs
> index f3de1e44..d1b61be9 100755
> --- a/i386/include/mach/i386/machine_types.defs
> +++ b/i386/include/mach/i386/machine_types.defs
> @@ -66,13 +66,25 @@ type long_natural_t = uint32_t;
>  #endif /* __x86_64__ */
>  
>  /*
> - * long_natural_t for kernel <-> userland interfaces as the size depends on 
> the
> - * architecture of both kernel and userland.
> + * Larger version of integer_t. Only used when we want to hold possibly 
> larger
> + * values than what is possible with integer_t.
> + */
> +#if defined(__x86_64__)
> +type long_integer_t = int64_t;
> +#else
> +type long_integer_t = int32_t;
> +#endif /* __x86_64__ */
> +
> +/*
> + * long_natural_t and long_integer_t for kernel <-> userland interfaces as 
> the
> + * size depends on the architecture of both kernel and userland.
>   */
>  #if defined(KERNEL) && defined(USER32)
>  type rpc_long_natural_t = uint32_t;
> +type rpc_long_integer_t = int32_t;
>  #else /* KERNEL and USER32 */
>  type rpc_long_natural_t = long_natural_t;
> +type rpc_long_integer_t = long_integer_t;
>  #endif /* KERNEL_SERVER and USER32 */
>  
>  /*
> diff --git a/i386/include/mach/i386/vm_types.h 
> b/i386/include/mach/i386/vm_types.h
> index 86e8563a..7e5857a5 100644
> --- a/i386/include/mach/i386/vm_types.h
> +++ b/i386/include/mach/i386/vm_types.h
> @@ -68,6 +68,12 @@ typedef int                integer_t;
>   */
>  typedef unsigned long long_natural_t;
>  
> +/*
> + * Larger version of integer_t. Only used when we want to hold possibly 
> larger
> + * values than what is possible with integer_t.
> + */
> +typedef long long_integer_t;
> +
>  /*
>   * A vm_offset_t is a type-neutral pointer,
>   * e.g. an offset into a virtual memory space.
> @@ -117,6 +123,7 @@ static inline __mach_uint32_t 
> convert_vm_to_user(__mach_uint64_t kaddr)
>      return (__mach_uint32_t)kaddr;
>  }
>  typedef __mach_uint32_t rpc_long_natural_t;
> +typedef __mach_int32_t rpc_long_integer_t;
>  #else /* MACH_KERNEL */
>  typedef vm_offset_t  rpc_vm_address_t;
>  typedef vm_offset_t  rpc_vm_offset_t;
> @@ -124,6 +131,7 @@ typedef vm_size_t rpc_vm_size_t;
>  #define convert_vm_to_user null_conversion
>  #define convert_vm_from_user null_conversion
>  typedef long_natural_t rpc_long_natural_t;
> +typedef long_integer_t rpc_long_integer_t;
>  #endif /* MACH_KERNEL */
>  
>  #endif       /* __ASSEMBLER__ */
> diff --git a/include/mach/mach_types.defs b/include/mach/mach_types.defs
> index 74b85232..da74a3f2 100644
> --- a/include/mach/mach_types.defs
> +++ b/include/mach/mach_types.defs
> @@ -261,7 +261,18 @@ type kernel_version_t            = 
> (MACH_MSG_TYPE_STRING, 512*8);
>  
>  type kernel_boot_info_t              = (MACH_MSG_TYPE_STRING, 4096*8);
>  
> -type time_value_t            = struct[2] of integer_t;
> +type rpc_time_value_t                = struct {
> +  rpc_long_integer_t seconds;
> +  integer_t microseconds;
> +};
> +type time_value_t = rpc_time_value_t
> +#if defined(KERNEL_SERVER)
> +    intran: time_value_t convert_time_value_from_user(rpc_time_value_t)
> +    outtran: rpc_time_value_t convert_time_value_to_user(time_value_t)
> +#elif defined(KERNEL_USER)
> +    ctype: rpc_time_value_t
> +#endif
> +    ;
>  
>  type emulation_vector_t              = ^array[] of vm_offset_t;
>  
> diff --git a/include/mach/time_value.h b/include/mach/time_value.h
> index 3a9c384c..53692bcf 100644
> --- a/include/mach/time_value.h
> +++ b/include/mach/time_value.h
> @@ -33,12 +33,37 @@
>   *   Time value returned by kernel.
>   */
>  
> +struct rpc_time_value {
> +     /* TODO: this should be 64 bits regardless of the arch to be Y2038 
> proof. */
> +     rpc_long_integer_t seconds;
> +     integer_t microseconds;
> +};
> +typedef struct rpc_time_value rpc_time_value_t;
> +
> +/*
> + *   Time value used by kernel.
> + */
>  struct time_value {
> -     integer_t       seconds;
> +     long_integer_t  seconds;
>       integer_t       microseconds;
>  };
>  typedef      struct time_value       time_value_t;
>  
> +/**
> + * Functions used by Mig to perform user to kernel conversion and vice-versa.
> + * We only do this because we may run a 64 bit kernel with a 32 bit user 
> space.
> + */
> +static inline rpc_time_value_t convert_time_value_to_user(time_value_t tv)
> +{
> +     rpc_time_value_t user = {.seconds = tv.seconds, .microseconds = 
> tv.microseconds};
> +     return user;
> +}
> +static inline time_value_t convert_time_value_from_user(rpc_time_value_t tv)
> +{
> +     time_value_t kernel = {.seconds = tv.seconds, .microseconds = 
> tv.microseconds};
> +     return kernel;
> +}
> +
>  /*
>   *   Macros to manipulate time values.  Assume that time values
>   *   are normalized (microseconds <= 999999).
> -- 
> 2.37.2
> 
> 

-- 
Samuel
---
Pour une évaluation indépendante, transparente et rigoureuse !
Je soutiens la Commission d'Évaluation de l'Inria.