[1/7] sysv: linux: Add 64-bit time_t variant for semctl

Message ID 20200630192441.3299710-1-adhemerval.zanella@linaro.org
State Superseded
Headers show
Series
  • [1/7] sysv: linux: Add 64-bit time_t variant for semctl
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Commit Message

Maciej W. Rozycki via Libc-alpha June 30, 2020, 7:24 p.m.
Different than others 64-bit time_t syscalls, the SysIPC interface
does not provide a new set of syscall for y2038 safeness.  Instead it
uses ununsed fields in semid_ds structure the return the high bits for
the timestamps.

To provide a y2038 safe interface a new symbol __semctl64 is added
and __semctl is change to call it instead (it adds some extra buffer
copy for the 32 bit time_t implementation).

Two two new structures are added:

  1. kernel_semid64_ds: used internally only on 32-bit architectures
     to issue the syscall.  A handful architectures (hppa, i386, mips,
     powerpc32, sparc32) requires specific implementation due its
     specific kernel ABI.

  2. semid_ds64: this is only for __TIMESIZE != 64 to use along with
     the 64-bit semctl.  It is different than the kernel one because
     the exported 64-bit time_t might require different alignment
     depending of the architecture ABI.

So the resulting implementation does:

  1. For 64-bit architectures it assumes semid_ds already contains
     64-bit time_t fields it will result in just the __semctl symbol
     using the __semctl64 code.  The semid_ds argument is passed as-is
     to the syscall.

  2. For 32-bit architectures with default 64-bit time_t (newer ABIs
     such riscv32 or arc), it will also result in only one exported
     symbol but with the required high/low handling.

     It might be possible to optimize it further to avoid the
     kernel_semid64_ds to semun transformation if the exported ABI
     for the architectures matches the expected kernel ABI, but the
     implementation is already complex enough and don't think this
     should be a hotspot in any case.

  3. Finally for 32-bit architecture with both 32-bit and 64-bit time_t
     support we follow the already set way to provide one symbol with
     64-bit time_t support and implement the 32-bit time_t support on
     basis of the 64-bit one.

     The default 32-bit symbol will allocate and copy the semid_ds
     over multiple buffers, but this should be deprecated in favor
     of the __semctl64 anyway.

Checked on i686-linux-gnu and x86_64-linux-gnu.  I also did some sniff
tests on powerpc, powerpc64, mips, mips64, armhf, sparcv9, and
sparc64.
---
 include/sys/sem.h                             |   7 +
 .../sysv/linux/bits/types/struct_semid64_ds.h |  33 +++
 .../sysv/linux/bits/types/struct_semid_ds.h   |  21 +-
 .../linux/hppa/bits/types/struct_semid_ds.h   |   6 +-
 .../linux/hppa/struct_kernel_semid64_ds.h     |  12 +
 .../linux/i386/struct_kernel_semid64_ds.h     |  12 +
 sysdeps/unix/sysv/linux/ipc_priv.h            |  10 +
 .../linux/mips/bits/types/struct_semid_ds.h   |   4 +-
 .../linux/mips/struct_kernel_semid64_ds.h     |  10 +
 .../powerpc/bits/types/struct_semid_ds.h      |   4 +-
 .../powerpc32/struct_kernel_semid64_ds.h      |  12 +
 sysdeps/unix/sysv/linux/semctl.c              | 261 +++++++++++++++---
 .../linux/sparc/bits/types/struct_semid_ds.h  |   4 +-
 .../sparc/sparc32/struct_kernel_semid64_ds.h  |  12 +
 .../sysv/linux/struct_kernel_semid64_ds.h     |  12 +
 .../linux/x86/bits/types/struct_semid_ds.h    |   4 +-
 16 files changed, 359 insertions(+), 65 deletions(-)
 create mode 100644 sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h
 create mode 100644 sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

-- 
2.25.1

Comments

Maciej W. Rozycki via Libc-alpha July 2, 2020, 7:01 p.m. | #1
On Tue, Jun 30, 2020 at 12:26 PM Adhemerval Zanella via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>

> Different than others 64-bit time_t syscalls, the SysIPC interface

> does not provide a new set of syscall for y2038 safeness.  Instead it

> uses ununsed fields in semid_ds structure the return the high bits for

> the timestamps.

>

> To provide a y2038 safe interface a new symbol __semctl64 is added

> and __semctl is change to call it instead (it adds some extra buffer

> copy for the 32 bit time_t implementation).

>

> Two two new structures are added:

>

>   1. kernel_semid64_ds: used internally only on 32-bit architectures

>      to issue the syscall.  A handful architectures (hppa, i386, mips,

>      powerpc32, sparc32) requires specific implementation due its

>      specific kernel ABI.

>

>   2. semid_ds64: this is only for __TIMESIZE != 64 to use along with

>      the 64-bit semctl.  It is different than the kernel one because

>      the exported 64-bit time_t might require different alignment

>      depending of the architecture ABI.

>

> So the resulting implementation does:

>

>   1. For 64-bit architectures it assumes semid_ds already contains

>      64-bit time_t fields it will result in just the __semctl symbol

>      using the __semctl64 code.  The semid_ds argument is passed as-is

>      to the syscall.

>

>   2. For 32-bit architectures with default 64-bit time_t (newer ABIs

>      such riscv32 or arc), it will also result in only one exported

>      symbol but with the required high/low handling.

>

>      It might be possible to optimize it further to avoid the

>      kernel_semid64_ds to semun transformation if the exported ABI

>      for the architectures matches the expected kernel ABI, but the

>      implementation is already complex enough and don't think this

>      should be a hotspot in any case.

>

>   3. Finally for 32-bit architecture with both 32-bit and 64-bit time_t

>      support we follow the already set way to provide one symbol with

>      64-bit time_t support and implement the 32-bit time_t support on

>      basis of the 64-bit one.

>

>      The default 32-bit symbol will allocate and copy the semid_ds

>      over multiple buffers, but this should be deprecated in favor

>      of the __semctl64 anyway.

>

> Checked on i686-linux-gnu and x86_64-linux-gnu.  I also did some sniff

> tests on powerpc, powerpc64, mips, mips64, armhf, sparcv9, and

> sparc64.


This looks good.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>


Alistair

> ---

>  include/sys/sem.h                             |   7 +

>  .../sysv/linux/bits/types/struct_semid64_ds.h |  33 +++

>  .../sysv/linux/bits/types/struct_semid_ds.h   |  21 +-

>  .../linux/hppa/bits/types/struct_semid_ds.h   |   6 +-

>  .../linux/hppa/struct_kernel_semid64_ds.h     |  12 +

>  .../linux/i386/struct_kernel_semid64_ds.h     |  12 +

>  sysdeps/unix/sysv/linux/ipc_priv.h            |  10 +

>  .../linux/mips/bits/types/struct_semid_ds.h   |   4 +-

>  .../linux/mips/struct_kernel_semid64_ds.h     |  10 +

>  .../powerpc/bits/types/struct_semid_ds.h      |   4 +-

>  .../powerpc32/struct_kernel_semid64_ds.h      |  12 +

>  sysdeps/unix/sysv/linux/semctl.c              | 261 +++++++++++++++---

>  .../linux/sparc/bits/types/struct_semid_ds.h  |   4 +-

>  .../sparc/sparc32/struct_kernel_semid64_ds.h  |  12 +

>  .../sysv/linux/struct_kernel_semid64_ds.h     |  12 +

>  .../linux/x86/bits/types/struct_semid_ds.h    |   4 +-

>  16 files changed, 359 insertions(+), 65 deletions(-)

>  create mode 100644 sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

>

> diff --git a/include/sys/sem.h b/include/sys/sem.h

> index 69fdf1f752..a9151e057d 100644

> --- a/include/sys/sem.h

> +++ b/include/sys/sem.h

> @@ -5,5 +5,12 @@

>

>  __typeof__ (semtimedop) __semtimedop attribute_hidden;

>

> +#if __TIMESIZE == 64

> +# define __semctl64 __semctl

> +#else

> +extern int __semctl64 (int semid, int semnum, int cmd, ...);

> +libc_hidden_proto (__semctl64);

> +#endif

> +

>  # endif

>  #endif

> diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

> new file mode 100644

> index 0000000000..bda9eb4469

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

> @@ -0,0 +1,33 @@

> +/* Generic implementation of the semaphore struct semid64_ds.

> +   Copyright (C) 2020 Free Software Foundation, Inc.

> +   This file is part of the GNU C Library.

> +

> +   The GNU C Library is free software; you can redistribute it and/or

> +   modify it under the terms of the GNU Lesser General Public

> +   License as published by the Free Software Foundation; either

> +   version 2.1 of the License, or (at your option) any later version.

> +

> +   The GNU C Library is distributed in the hope that it will be useful,

> +   but WITHOUT ANY WARRANTY; without even the implied warranty of

> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

> +   Lesser General Public License for more details.

> +

> +   You should have received a copy of the GNU Lesser General Public

> +   License along with the GNU C Library; if not, see

> +   <https://www.gnu.org/licenses/>.  */

> +

> +#ifndef _SYS_SEM_H

> +# error "Never include <bits/types/struct_semid_ds.h> directly; use <sys/sem.h> instead."

> +#endif

> +

> +#if __TIMESIZE == 64

> +# define __semid64_ds semid_ds

> +#else

> +struct __semid64_ds

> +{

> +  struct ipc_perm sem_perm;            /* operation permission struct */

> +  __time64_t sem_otime;                        /* last semop() time */

> +  __time64_t sem_ctime;                        /* last time changed by semctl() */

> +  __syscall_ulong_t sem_nsems;         /* number of semaphores in set */

> +};

> +#endif

> diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> index 4222e6a59f..bc26d8be08 100644

> --- a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> @@ -21,26 +21,19 @@

>  #endif

>

>  /* Data structure describing a set of semaphores.  */

> -#if __TIMESIZE == 32

>  struct semid_ds

>  {

>    struct ipc_perm sem_perm;        /* operation permission struct */

> +#if __TIMESIZE == 32

>    __time_t sem_otime;              /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_ctime;             /* last time changed by semctl() */

> -  __syscall_ulong_t __glibc_reserved2;

> -  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

> -  __syscall_ulong_t __glibc_reserved3;

> -  __syscall_ulong_t __glibc_reserved4;

> -};

> +  __syscall_ulong_t __sem_ctime_high;

>  #else

> -struct semid_ds

> -{

> -  struct ipc_perm sem_perm;            /* operation permission struct */

> -  __time_t sem_otime;                  /* last semop() time */

> -  __time_t sem_ctime;                  /* last time changed by semctl() */

> -  __syscall_ulong_t sem_nsems;         /* number of semaphores in set */

> +  __time_t sem_otime;

> +  __time_t sem_ctime;

> +#endif

> +  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

>  };

> -#endif

> diff --git a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> index d4c50b5ef8..68f9eca24c 100644

> --- a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> @@ -21,16 +21,14 @@

>  #endif

>

>  /* Data structure describing a set of semaphores.  */

> -#if __TIMESIZE == 32

>  struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;

>    __time_t sem_ctime;         /* last time changed by semctl() */

>    __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

>  };

> -#endif

> diff --git a/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..2871030d0d

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long __ununsed1;

> +  unsigned long __ununsed2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..bab9cf63ba

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_ctime_high;

> +  __syscall_ulong_t sem_nsems;

> +  __syscall_ulong_t __unused3;

> +  __syscall_ulong_t __unused4;

> +};

> diff --git a/sysdeps/unix/sysv/linux/ipc_priv.h b/sysdeps/unix/sysv/linux/ipc_priv.h

> index 15a6e683a4..93a6e5cb24 100644

> --- a/sysdeps/unix/sysv/linux/ipc_priv.h

> +++ b/sysdeps/unix/sysv/linux/ipc_priv.h

> @@ -53,4 +53,14 @@ struct __old_ipc_perm

>  #define SEMTIMEDOP_IPC_ARGS(__nsops, __sops, __timeout) \

>    (__nsops), 0, (__sops), (__timeout)

>

> +/* Linux SysV ipc does not provide new syscalls for 64-bit time support on

> +   32-bit architectures, but rather split the timestamps on previous unused

> +   fields.  */

> +#if (__WORDSIZE == 32 \

> +     && (!defined __SYSCALL_WORDSIZE || __SYSCALL_WORDSIZE == 32))

> +# define __IPC_TIME64 1

> +#else

> +# define __IPC_TIME64 0

> +#endif

> +

>  #include <ipc_ops.h>

> diff --git a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> index 8954209a29..eec4a18cae 100644

> --- a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> @@ -27,6 +27,6 @@ struct semid_ds

>    __time_t sem_otime;  /* last semop() time */

>    __time_t sem_ctime;  /* last time changed by semctl() */

>    __syscall_ulong_t sem_nsems;         /* number of semaphores in set */

> -  __syscall_ulong_t __glibc_reserved3;

> -  __syscall_ulong_t __glibc_reserved4;

> +  __syscall_ulong_t __sem_otime_high;

> +  __syscall_ulong_t __sem_ctime_high;

>  };

> diff --git a/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..76a9d83ea5

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

> @@ -0,0 +1,10 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime_high;

> +};

> diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> index 300a9b98e9..d382d93c52 100644

> --- a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>  #if __TIMESIZE == 32

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;

>    __time_t sem_ctime;        /* last time changed by semctl() */

>  #else

>    __time_t sem_otime;         /* last semop() time */

> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..7fa4ef6424

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long __unused3;

> +  unsigned long __unused4;

> +};

> diff --git a/sysdeps/unix/sysv/linux/semctl.c b/sysdeps/unix/sysv/linux/semctl.c

> index 30571af49f..3a06270242 100644

> --- a/sysdeps/unix/sysv/linux/semctl.c

> +++ b/sysdeps/unix/sysv/linux/semctl.c

> @@ -21,10 +21,13 @@

>  #include <ipc_priv.h>

>  #include <sysdep.h>

>  #include <shlib-compat.h>

> -#include <errno.h>

> -#include <linux/posix_types.h>  /* For __kernel_mode_t.  */

> +#include <bits/types/struct_semid64_ds.h>  /* For __semid64_ds.  */

> +#include <linux/posix_types.h>             /* For __kernel_mode_t.  */

>

> -/* Define a `union semun' suitable for Linux here.  */

> +/* The struct used to issue the syscall.  For architecture that assume

> +   64-bit time as default (!__ASSUME_TIME64_SYSCALLS) the syscall will

> +   split the resulting 64-bit sem_{o,c}time in two fields (__sem_{o,c}time

> +   and __sem_{o,c}time_hi).  */

>  union semun

>  {

>    int val;                     /* value for SETVAL */

> @@ -33,16 +36,89 @@ union semun

>    struct seminfo *__buf;       /* buffer for IPC_INFO */

>  };

>

> -#ifndef DEFAULT_VERSION

> -# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -#  define DEFAULT_VERSION GLIBC_2_2

> +#if __IPC_TIME64 == 0

> +# define semun64 semun

> +typedef union semun semctl_arg_t;

> +#else

> +# include <struct_kernel_semid64_ds.h>

> +

> +union ksemun64

> +{

> +  int val;

> +  struct kernel_semid64_ds *buf;

> +  unsigned short int *array;

> +  struct seminfo *__buf;

> +};

> +

> +# if __TIMESIZE == 64

> +#  define semun64 semun

>  # else

> -#  define DEFAULT_VERSION GLIBC_2_31

> +/* The struct used when __semctl64 is called.  */

> +union semun64

> +{

> +  int val;

> +  struct __semid64_ds *buf;

> +  unsigned short int *array;

> +  struct seminfo *__buf;

> +};

>  # endif

> +

> +static void

> +semid64_to_ksemid64 (const struct __semid64_ds *semid64,

> +                    struct kernel_semid64_ds *ksemid)

> +{

> +  ksemid->sem_perm       = semid64->sem_perm;

> +  ksemid->sem_otime      = semid64->sem_otime;

> +  ksemid->sem_otime_high = semid64->sem_otime >> 32;

> +  ksemid->sem_ctime      = semid64->sem_ctime;

> +  ksemid->sem_ctime_high = semid64->sem_ctime >> 32;

> +  ksemid->sem_nsems      = semid64->sem_nsems;

> +}

> +

> +static void

> +ksemid64_to_semid64 (const struct kernel_semid64_ds *ksemid,

> +                    struct __semid64_ds *semid64)

> +{

> +  semid64->sem_perm  = ksemid->sem_perm;

> +  semid64->sem_otime = ksemid->sem_otime

> +                      | ((__time64_t) ksemid->sem_otime_high << 32);

> +  semid64->sem_ctime = ksemid->sem_ctime

> +                      | ((__time64_t) ksemid->sem_ctime_high << 32);

> +  semid64->sem_nsems = ksemid->sem_nsems;

> +}

> +

> +static union ksemun64

> +semun64_to_ksemun64 (int cmd, union semun64 semun64,

> +                    struct kernel_semid64_ds *buf)

> +{

> +  union ksemun64 r = { 0 };

> +  switch (cmd)

> +    {

> +    case SETVAL:

> +      r.val = semun64.val;

> +      break;

> +    case GETALL:

> +    case SETALL:

> +      r.array = semun64.array;

> +      break;

> +    case IPC_STAT:

> +    case IPC_SET:

> +      r.buf = buf;

> +      semid64_to_ksemid64 (semun64.buf, r.buf);

> +      break;

> +    case IPC_INFO:

> +    case SEM_INFO:

> +      r.__buf = semun64.__buf;

> +      break;

> +    }

> +  return r;

> +}

> +

> +typedef union ksemun64 semctl_arg_t;

>  #endif

>

>  static int

> -semctl_syscall (int semid, int semnum, int cmd, union semun arg)

> +semctl_syscall (int semid, int semnum, int cmd, semctl_arg_t arg)

>  {

>  #ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS

>    return INLINE_SYSCALL_CALL (semctl, semid, semnum, cmd | __IPC_64,

> @@ -53,15 +129,15 @@ semctl_syscall (int semid, int semnum, int cmd, union semun arg)

>  #endif

>  }

>

> +/* POSIX states ipc_perm mode should have type of mode_t.  */

> +_Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)

> +               == sizeof (mode_t),

> +               "sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");

> +

>  int

> -__new_semctl (int semid, int semnum, int cmd, ...)

> +__semctl64 (int semid, int semnum, int cmd, ...)

>  {

> -  /* POSIX states ipc_perm mode should have type of mode_t.  */

> -  _Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)

> -                 == sizeof (mode_t),

> -                 "sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");

> -

> -  union semun arg = { 0 };

> +  union semun64 arg64 = { 0 };

>    va_list ap;

>

>    /* Get the argument only if required.  */

> @@ -76,44 +152,151 @@ __new_semctl (int semid, int semnum, int cmd, ...)

>      case IPC_INFO:      /* arg.__buf */

>      case SEM_INFO:

>        va_start (ap, cmd);

> -      arg = va_arg (ap, union semun);

> +      arg64 = va_arg (ap, union semun64);

>        va_end (ap);

>        break;

>      }

>

> -#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -  struct semid_ds tmpds;

> -  if (cmd == IPC_SET)

> -    {

> -      tmpds = *arg.buf;

> -      tmpds.sem_perm.mode *= 0x10000U;

> -      arg.buf = &tmpds;

> -    }

> +#if __IPC_TIME64

> +  struct kernel_semid64_ds ksemid;

> +  union ksemun64 ksemun = semun64_to_ksemun64 (cmd, arg64, &ksemid);

> +  union ksemun64 arg = ksemun;

> +#else

> +  union semun arg = arg64;

>  #endif

>

>    int ret = semctl_syscall (semid, semnum, cmd, arg);

> +  if (ret < 0)

> +    return ret;

>

> -  if (ret >= 0)

> +  switch (cmd)

>      {

> -      switch (cmd)

> -       {

> -        case IPC_STAT:

> -        case SEM_STAT:

> -        case SEM_STAT_ANY:

> +    case IPC_STAT:

> +    case SEM_STAT:

> +    case SEM_STAT_ANY:

>  #ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -          arg.buf->sem_perm.mode >>= 16;

> +      arg.buf->sem_perm.mode >>= 16;

>  #else

> -         /* Old Linux kernel versions might not clear the mode padding.  */

> -         if (sizeof ((struct semid_ds){0}.sem_perm.mode)

> -             != sizeof (__kernel_mode_t))

> -           arg.buf->sem_perm.mode &= 0xFFFF;

> +      /* Old Linux kernel versions might not clear the mode padding.  */

> +      if (sizeof ((struct semid_ds){0}.sem_perm.mode)

> +         != sizeof (__kernel_mode_t))

> +       arg.buf->sem_perm.mode &= 0xFFFF;

>  #endif

> -       }

> +

> +#if __IPC_TIME64

> +      ksemid64_to_semid64 (arg.buf, arg64.buf);

> +#endif

> +    }

> +

> +  return ret;

> +}

> +#if __TIMESIZE != 64

> +libc_hidden_def (__semctl64)

> +

> +

> +/* The 64-bit time_t semid_ds version might have a different layout and

> +   internal field alignment.  */

> +static void

> +semid64_ds_to_semid_ds (struct semid_ds *ds, const struct __semid64_ds *ds64)

> +{

> +  ds->sem_perm = ds64->sem_perm;

> +  ds->sem_otime = ds64->sem_otime;

> +  ds->sem_ctime = ds64->sem_ctime;

> +  ds->sem_nsems = ds64->sem_nsems;

> +}

> +

> +static void

> +semid_ds_to_semid64_ds (struct __semid64_ds *ds64, const struct semid_ds *ds)

> +{

> +  ds64->sem_perm = ds->sem_perm;

> +  ds64->sem_otime = ds->sem_otime

> +                   | ((__time64_t) ds->__sem_otime_high << 32);

> +  ds64->sem_ctime = ds->sem_ctime

> +                   | ((__time64_t) ds->__sem_ctime_high << 32);

> +  ds64->sem_nsems = ds->sem_nsems;

> +}

> +

> +static union semun64

> +semun_to_semun64 (int cmd, union semun semun, struct __semid64_ds *semid64)

> +{

> +  union semun64 r = { 0 };

> +  switch (cmd)

> +    {

> +    case SETVAL:

> +      r.val = semun.val;

> +      break;

> +    case GETALL:

> +    case SETALL:

> +      r.array = semun.array;

> +      break;

> +    case IPC_STAT:

> +    case IPC_SET:

> +      r.buf = semid64;

> +      semid_ds_to_semid64_ds (r.buf, semun.buf);

> +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> +      if (cmd == IPC_SET)

> +       r.buf->sem_perm.mode *= 0x10000U;

> +# endif

> +      break;

> +    case IPC_INFO:

> +    case SEM_INFO:

> +      r.__buf = semun.__buf;

> +      break;

> +    }

> +  return r;

> +}

> +

> +int

> +__semctl (int semid, int semnum, int cmd, ...)

> +{

> +  union semun arg = { 0 };

> +

> +  va_list ap;

> +

> +  /* Get the argument only if required.  */

> +  switch (cmd)

> +    {

> +    case SETVAL:        /* arg.val */

> +    case GETALL:        /* arg.array */

> +    case SETALL:

> +    case IPC_STAT:      /* arg.buf */

> +    case IPC_SET:

> +    case SEM_STAT:

> +    case IPC_INFO:      /* arg.__buf */

> +    case SEM_INFO:

> +      va_start (ap, cmd);

> +      arg = va_arg (ap, union semun);

> +      va_end (ap);

> +      break;

> +    }

> +

> +  struct __semid64_ds semid64;

> +  union semun64 arg64 = semun_to_semun64 (cmd, arg, &semid64);

> +

> +  int ret = __semctl64 (semid, semnum, cmd, arg64);

> +  if (ret < 0)

> +    return ret;

> +

> +  switch (cmd)

> +    {

> +    case IPC_STAT:

> +    case SEM_STAT:

> +    case SEM_STAT_ANY:

> +      semid64_ds_to_semid_ds (arg.buf, arg64.buf);

>      }

>

>    return ret;

>  }

> -versioned_symbol (libc, __new_semctl, semctl, DEFAULT_VERSION);

> +#endif

> +

> +#ifndef DEFAULT_VERSION

> +# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T

> +#  define DEFAULT_VERSION GLIBC_2_2

> +# else

> +#  define DEFAULT_VERSION GLIBC_2_31

> +# endif

> +#endif

> +versioned_symbol (libc, __semctl, semctl, DEFAULT_VERSION);

>

>  #if defined __ASSUME_SYSVIPC_BROKEN_MODE_T \

>      && SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_31)

> @@ -121,7 +304,7 @@ int

>  attribute_compat_text_section

>  __semctl_mode16 (int semid, int semnum, int cmd, ...)

>  {

> -  union semun arg = { 0 };

> +  semctl_arg_t arg = { 0 };

>    va_list ap;

>

>    /* Get the argument only if required.  */

> @@ -136,7 +319,7 @@ __semctl_mode16 (int semid, int semnum, int cmd, ...)

>      case IPC_INFO:      /* arg.__buf */

>      case SEM_INFO:

>        va_start (ap, cmd);

> -      arg = va_arg (ap, union semun);

> +      arg = va_arg (ap, semctl_arg_t);

>        va_end (ap);

>        break;

>      }

> diff --git a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> index 46fcd79fb6..0110c1a940 100644

> --- a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>  #if __TIMESIZE == 32

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;

>    __time_t sem_ctime;        /* last time changed by semctl() */

>  #else

>    __time_t sem_otime;         /* last semop() time */

> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..8c4697f9ab

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long __unused1;

> +  unsigned long __unused2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..f9edf0f76f

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_nsems;

> +  unsigned long __unused1;

> +  unsigned long __unused2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> index f7ec89d115..c3f2fde9fd 100644

> --- a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>    __time_t sem_otime;  /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_ctime;  /* last time changed by semctl() */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;

>    __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

> --

> 2.25.1

>
Maciej W. Rozycki via Libc-alpha July 7, 2020, 3:32 a.m. | #2
On 6/30/20 3:24 PM, Adhemerval Zanella via Libc-alpha wrote:

OK for master with comment cleanups. Very clean, very easy to understand
patch. I should finish the other 6 patches tomorrow morning.

No regressions on x86_64 or i686 (I did see the new rseq regression
for posix/tst-affinity-static though).

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

Tested-by: Carlos O'Donell <carlos@redhat.com>


> Different than others 64-bit time_t syscalls, the SysIPC interface

> does not provide a new set of syscall for y2038 safeness.  Instead it

> uses ununsed fields in semid_ds structure the return the high bits for


s/ununsed/unused/g
s/the return/to return/g

> the timestamps.

> 

> To provide a y2038 safe interface a new symbol __semctl64 is added

> and __semctl is change to call it instead (it adds some extra buffer

> copy for the 32 bit time_t implementation).


OK.

> 

> Two two new structures are added:


s/Two two/Two/g

> 

>   1. kernel_semid64_ds: used internally only on 32-bit architectures

>      to issue the syscall.  A handful architectures (hppa, i386, mips,


s/handful/handful of/g

>      powerpc32, sparc32) requires specific implementation due its

>      specific kernel ABI.


Suggest:

require specific implementations due to their kernel ABI.

> 

>   2. semid_ds64: this is only for __TIMESIZE != 64 to use along with

>      the 64-bit semctl.  It is different than the kernel one because


s/one/struct/g

>      the exported 64-bit time_t might require different alignment

>      depending of the architecture ABI.


OK.

> 

> So the resulting implementation does:

> 

>   1. For 64-bit architectures it assumes semid_ds already contains

>      64-bit time_t fields it will result in just the __semctl symbol


s/it/and/g

>      using the __semctl64 code.  The semid_ds argument is passed as-is

>      to the syscall.

> 

>   2. For 32-bit architectures with default 64-bit time_t (newer ABIs

>      such riscv32 or arc), it will also result in only one exported

>      symbol but with the required high/low handling.


OK.
 
>      It might be possible to optimize it further to avoid the

>      kernel_semid64_ds to semun transformation if the exported ABI

>      for the architectures matches the expected kernel ABI, but the

>      implementation is already complex enough and don't think this

>      should be a hotspot in any case.


OK. Agreed. If we see a hotspot here we can discuss.

>   3. Finally for 32-bit architecture with both 32-bit and 64-bit time_t

>      support we follow the already set way to provide one symbol with

>      64-bit time_t support and implement the 32-bit time_t support on

>      basis of the 64-bit one.


s/on basis of/using/g
s/one/time_t/g
 
>      The default 32-bit symbol will allocate and copy the semid_ds

>      over multiple buffers, but this should be deprecated in favor

>      of the __semctl64 anyway.


OK.

> 

> Checked on i686-linux-gnu and x86_64-linux-gnu.  I also did some sniff

> tests on powerpc, powerpc64, mips, mips64, armhf, sparcv9, and

> sparc64.


OK.

> ---

>  include/sys/sem.h                             |   7 +

>  .../sysv/linux/bits/types/struct_semid64_ds.h |  33 +++

>  .../sysv/linux/bits/types/struct_semid_ds.h   |  21 +-

>  .../linux/hppa/bits/types/struct_semid_ds.h   |   6 +-

>  .../linux/hppa/struct_kernel_semid64_ds.h     |  12 +

>  .../linux/i386/struct_kernel_semid64_ds.h     |  12 +

>  sysdeps/unix/sysv/linux/ipc_priv.h            |  10 +

>  .../linux/mips/bits/types/struct_semid_ds.h   |   4 +-

>  .../linux/mips/struct_kernel_semid64_ds.h     |  10 +

>  .../powerpc/bits/types/struct_semid_ds.h      |   4 +-

>  .../powerpc32/struct_kernel_semid64_ds.h      |  12 +

>  sysdeps/unix/sysv/linux/semctl.c              | 261 +++++++++++++++---

>  .../linux/sparc/bits/types/struct_semid_ds.h  |   4 +-

>  .../sparc/sparc32/struct_kernel_semid64_ds.h  |  12 +

>  .../sysv/linux/struct_kernel_semid64_ds.h     |  12 +

>  .../linux/x86/bits/types/struct_semid_ds.h    |   4 +-

>  16 files changed, 359 insertions(+), 65 deletions(-)

>  create mode 100644 sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

>  create mode 100644 sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

> 

> diff --git a/include/sys/sem.h b/include/sys/sem.h

> index 69fdf1f752..a9151e057d 100644

> --- a/include/sys/sem.h

> +++ b/include/sys/sem.h

> @@ -5,5 +5,12 @@

>  

>  __typeof__ (semtimedop) __semtimedop attribute_hidden;

>  

> +#if __TIMESIZE == 64

> +# define __semctl64 __semctl

> +#else

> +extern int __semctl64 (int semid, int semnum, int cmd, ...);

> +libc_hidden_proto (__semctl64);


OK.

> +#endif

> +

>  # endif

>  #endif

> diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

> new file mode 100644

> index 0000000000..bda9eb4469

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h

> @@ -0,0 +1,33 @@

> +/* Generic implementation of the semaphore struct semid64_ds.

> +   Copyright (C) 2020 Free Software Foundation, Inc.

> +   This file is part of the GNU C Library.

> +

> +   The GNU C Library is free software; you can redistribute it and/or

> +   modify it under the terms of the GNU Lesser General Public

> +   License as published by the Free Software Foundation; either

> +   version 2.1 of the License, or (at your option) any later version.

> +

> +   The GNU C Library is distributed in the hope that it will be useful,

> +   but WITHOUT ANY WARRANTY; without even the implied warranty of

> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

> +   Lesser General Public License for more details.

> +

> +   You should have received a copy of the GNU Lesser General Public

> +   License along with the GNU C Library; if not, see

> +   <https://www.gnu.org/licenses/>.  */

> +

> +#ifndef _SYS_SEM_H

> +# error "Never include <bits/types/struct_semid_ds.h> directly; use <sys/sem.h> instead."

> +#endif

> +

> +#if __TIMESIZE == 64

> +# define __semid64_ds semid_ds

> +#else

> +struct __semid64_ds

> +{

> +  struct ipc_perm sem_perm;		/* operation permission struct */


OK.

> +  __time64_t sem_otime;			/* last semop() time */

> +  __time64_t sem_ctime;			/* last time changed by semctl() */

> +  __syscall_ulong_t sem_nsems;		/* number of semaphores in set */


OK.

> +};

> +#endif

> diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> index 4222e6a59f..bc26d8be08 100644

> --- a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h

> @@ -21,26 +21,19 @@

>  #endif

>  

>  /* Data structure describing a set of semaphores.  */

> -#if __TIMESIZE == 32

>  struct semid_ds

>  {

>    struct ipc_perm sem_perm;        /* operation permission struct */

> +#if __TIMESIZE == 32

>    __time_t sem_otime;              /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;


OK.

>    __time_t sem_ctime;             /* last time changed by semctl() */

> -  __syscall_ulong_t __glibc_reserved2;

> -  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

> -  __syscall_ulong_t __glibc_reserved3;

> -  __syscall_ulong_t __glibc_reserved4;

> -};

> +  __syscall_ulong_t __sem_ctime_high;


OK.

>  #else

> -struct semid_ds

> -{

> -  struct ipc_perm sem_perm;		/* operation permission struct */

> -  __time_t sem_otime;			/* last semop() time */

> -  __time_t sem_ctime;			/* last time changed by semctl() */

> -  __syscall_ulong_t sem_nsems;		/* number of semaphores in set */

> +  __time_t sem_otime;

> +  __time_t sem_ctime;


OK.

> +#endif

> +  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */


OK.

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

>  };

> -#endif

> diff --git a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> index d4c50b5ef8..68f9eca24c 100644

> --- a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h

> @@ -21,16 +21,14 @@

>  #endif

>  

>  /* Data structure describing a set of semaphores.  */

> -#if __TIMESIZE == 32

>  struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;


OK.

>    __time_t sem_ctime;         /* last time changed by semctl() */

>    __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

>  };

> -#endif

> diff --git a/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..2871030d0d

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;


OK. Matches where the reserved entries were for hppa.

> +  unsigned long sem_nsems;

> +  unsigned long __ununsed1;

> +  unsigned long __ununsed2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..bab9cf63ba

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_ctime_high;


OK.

> +  __syscall_ulong_t sem_nsems;

> +  __syscall_ulong_t __unused3;

> +  __syscall_ulong_t __unused4;

> +};

> diff --git a/sysdeps/unix/sysv/linux/ipc_priv.h b/sysdeps/unix/sysv/linux/ipc_priv.h

> index 15a6e683a4..93a6e5cb24 100644

> --- a/sysdeps/unix/sysv/linux/ipc_priv.h

> +++ b/sysdeps/unix/sysv/linux/ipc_priv.h

> @@ -53,4 +53,14 @@ struct __old_ipc_perm

>  #define SEMTIMEDOP_IPC_ARGS(__nsops, __sops, __timeout) \

>    (__nsops), 0, (__sops), (__timeout)

>  

> +/* Linux SysV ipc does not provide new syscalls for 64-bit time support on

> +   32-bit architectures, but rather split the timestamps on previous unused

> +   fields.  */


Suggest:

but rather split the timestamp into high and low; storing the high value in
previously unused fields.

> +#if (__WORDSIZE == 32 \

> +     && (!defined __SYSCALL_WORDSIZE || __SYSCALL_WORDSIZE == 32))

> +# define __IPC_TIME64 1

> +#else

> +# define __IPC_TIME64 0

> +#endif


OK.

> +

>  #include <ipc_ops.h>

> diff --git a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> index 8954209a29..eec4a18cae 100644

> --- a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h

> @@ -27,6 +27,6 @@ struct semid_ds

>    __time_t sem_otime;	/* last semop() time */

>    __time_t sem_ctime;	/* last time changed by semctl() */

>    __syscall_ulong_t sem_nsems;		/* number of semaphores in set */

> -  __syscall_ulong_t __glibc_reserved3;

> -  __syscall_ulong_t __glibc_reserved4;

> +  __syscall_ulong_t __sem_otime_high;

> +  __syscall_ulong_t __sem_ctime_high;


OK.

>  };

> diff --git a/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..76a9d83ea5

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h

> @@ -0,0 +1,10 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime_high;


OK. Matches mips.

> +};

> diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> index 300a9b98e9..d382d93c52 100644

> --- a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>  #if __TIMESIZE == 32

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;


OK.

>    __time_t sem_ctime;        /* last time changed by semctl() */

>  #else

>    __time_t sem_otime;         /* last semop() time */

> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..7fa4ef6424

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_nsems;

> +  unsigned long __unused3;

> +  unsigned long __unused4;


OK. Matches powerpc32.

> +};

> diff --git a/sysdeps/unix/sysv/linux/semctl.c b/sysdeps/unix/sysv/linux/semctl.c

> index 30571af49f..3a06270242 100644

> --- a/sysdeps/unix/sysv/linux/semctl.c

> +++ b/sysdeps/unix/sysv/linux/semctl.c

> @@ -21,10 +21,13 @@

>  #include <ipc_priv.h>

>  #include <sysdep.h>

>  #include <shlib-compat.h>

> -#include <errno.h>

> -#include <linux/posix_types.h>  /* For __kernel_mode_t.  */

> +#include <bits/types/struct_semid64_ds.h>  /* For __semid64_ds.  */

> +#include <linux/posix_types.h>             /* For __kernel_mode_t.  */


OK.

>  

> -/* Define a `union semun' suitable for Linux here.  */

> +/* The struct used to issue the syscall.  For architecture that assume


s/architecture/architectures/g

> +   64-bit time as default (!__ASSUME_TIME64_SYSCALLS) the syscall will

> +   split the resulting 64-bit sem_{o,c}time in two fields (__sem_{o,c}time


s/__sem_{o,c}time/sem_{o,c}time/g

> +   and __sem_{o,c}time_hi).  */


s/__sem_{o,c}time_hi/__sem{o,c}time_high/g

>  union semun

>  {

>    int val;			/* value for SETVAL */

> @@ -33,16 +36,89 @@ union semun

>    struct seminfo *__buf;	/* buffer for IPC_INFO */

>  };

>  

> -#ifndef DEFAULT_VERSION

> -# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -#  define DEFAULT_VERSION GLIBC_2_2

> +#if __IPC_TIME64 == 0

> +# define semun64 semun

> +typedef union semun semctl_arg_t;

> +#else

> +# include <struct_kernel_semid64_ds.h>

> +

> +union ksemun64

> +{

> +  int val;

> +  struct kernel_semid64_ds *buf;

> +  unsigned short int *array;

> +  struct seminfo *__buf;

> +};


OK. Kernel side.

> +

> +# if __TIMESIZE == 64

> +#  define semun64 semun

>  # else

> -#  define DEFAULT_VERSION GLIBC_2_31

> +/* The struct used when __semctl64 is called.  */

> +union semun64

> +{

> +  int val;

> +  struct __semid64_ds *buf;

> +  unsigned short int *array;

> +  struct seminfo *__buf;

> +};


OK. User side.

>  # endif

> +

> +static void

> +semid64_to_ksemid64 (const struct __semid64_ds *semid64,

> +		     struct kernel_semid64_ds *ksemid)

> +{

> +  ksemid->sem_perm       = semid64->sem_perm;

> +  ksemid->sem_otime      = semid64->sem_otime;

> +  ksemid->sem_otime_high = semid64->sem_otime >> 32;

> +  ksemid->sem_ctime      = semid64->sem_ctime;

> +  ksemid->sem_ctime_high = semid64->sem_ctime >> 32;

> +  ksemid->sem_nsems      = semid64->sem_nsems;

> +}


OK. Copy to kernel.

> +

> +static void

> +ksemid64_to_semid64 (const struct kernel_semid64_ds *ksemid,

> +		     struct __semid64_ds *semid64)

> +{

> +  semid64->sem_perm  = ksemid->sem_perm;

> +  semid64->sem_otime = ksemid->sem_otime

> +		       | ((__time64_t) ksemid->sem_otime_high << 32);

> +  semid64->sem_ctime = ksemid->sem_ctime

> +		       | ((__time64_t) ksemid->sem_ctime_high << 32);

> +  semid64->sem_nsems = ksemid->sem_nsems;

> +}


OK. Copy to user (full 64-bit wide).

> +

> +static union ksemun64

> +semun64_to_ksemun64 (int cmd, union semun64 semun64,

> +		     struct kernel_semid64_ds *buf)

> +{

> +  union ksemun64 r = { 0 };

> +  switch (cmd)

> +    {

> +    case SETVAL:

> +      r.val = semun64.val;

> +      break;

> +    case GETALL:

> +    case SETALL:

> +      r.array = semun64.array;

> +      break;

> +    case IPC_STAT:

> +    case IPC_SET:

> +      r.buf = buf;

> +      semid64_to_ksemid64 (semun64.buf, r.buf);

> +      break;

> +    case IPC_INFO:

> +    case SEM_INFO:

> +      r.__buf = semun64.__buf;

> +      break;

> +    }

> +  return r;

> +}


OK. Union copy.

> +

> +typedef union ksemun64 semctl_arg_t;

>  #endif

>  

>  static int

> -semctl_syscall (int semid, int semnum, int cmd, union semun arg)

> +semctl_syscall (int semid, int semnum, int cmd, semctl_arg_t arg)

>  {

>  #ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS

>    return INLINE_SYSCALL_CALL (semctl, semid, semnum, cmd | __IPC_64,

> @@ -53,15 +129,15 @@ semctl_syscall (int semid, int semnum, int cmd, union semun arg)

>  #endif

>  }

>  

> +/* POSIX states ipc_perm mode should have type of mode_t.  */

> +_Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)

> +		== sizeof (mode_t),

> +		"sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");


OK.

> +

>  int

> -__new_semctl (int semid, int semnum, int cmd, ...)

> +__semctl64 (int semid, int semnum, int cmd, ...)

>  {

> -  /* POSIX states ipc_perm mode should have type of mode_t.  */

> -  _Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)

> -		  == sizeof (mode_t),

> -		  "sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");

> -

> -  union semun arg = { 0 };

> +  union semun64 arg64 = { 0 };

>    va_list ap;

>  

>    /* Get the argument only if required.  */

> @@ -76,44 +152,151 @@ __new_semctl (int semid, int semnum, int cmd, ...)

>      case IPC_INFO:      /* arg.__buf */

>      case SEM_INFO:

>        va_start (ap, cmd);

> -      arg = va_arg (ap, union semun);

> +      arg64 = va_arg (ap, union semun64);

>        va_end (ap);

>        break;

>      }

>  

> -#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -  struct semid_ds tmpds;

> -  if (cmd == IPC_SET)

> -    {

> -      tmpds = *arg.buf;

> -      tmpds.sem_perm.mode *= 0x10000U;

> -      arg.buf = &tmpds;

> -    }

> +#if __IPC_TIME64

> +  struct kernel_semid64_ds ksemid;

> +  union ksemun64 ksemun = semun64_to_ksemun64 (cmd, arg64, &ksemid);

> +  union ksemun64 arg = ksemun;

> +#else

> +  union semun arg = arg64;

>  #endif

>  

>    int ret = semctl_syscall (semid, semnum, cmd, arg);

> +  if (ret < 0)

> +    return ret;

>  

> -  if (ret >= 0)

> +  switch (cmd)

>      {

> -      switch (cmd)

> -	{

> -        case IPC_STAT:

> -        case SEM_STAT:

> -        case SEM_STAT_ANY:

> +    case IPC_STAT:

> +    case SEM_STAT:

> +    case SEM_STAT_ANY:

>  #ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> -          arg.buf->sem_perm.mode >>= 16;

> +      arg.buf->sem_perm.mode >>= 16;

>  #else

> -	  /* Old Linux kernel versions might not clear the mode padding.  */

> -	  if (sizeof ((struct semid_ds){0}.sem_perm.mode)

> -	      != sizeof (__kernel_mode_t))

> -	    arg.buf->sem_perm.mode &= 0xFFFF;

> +      /* Old Linux kernel versions might not clear the mode padding.  */

> +      if (sizeof ((struct semid_ds){0}.sem_perm.mode)

> +	  != sizeof (__kernel_mode_t))

> +	arg.buf->sem_perm.mode &= 0xFFFF;

>  #endif

> -	}

> +

> +#if __IPC_TIME64

> +      ksemid64_to_semid64 (arg.buf, arg64.buf);

> +#endif

> +    }

> +

> +  return ret;

> +}


OK.

> +#if __TIMESIZE != 64

> +libc_hidden_def (__semctl64)

> +

> +

> +/* The 64-bit time_t semid_ds version might have a different layout and

> +   internal field alignment.  */

> +static void

> +semid64_ds_to_semid_ds (struct semid_ds *ds, const struct __semid64_ds *ds64)

> +{

> +  ds->sem_perm = ds64->sem_perm;

> +  ds->sem_otime = ds64->sem_otime;

> +  ds->sem_ctime = ds64->sem_ctime;

> +  ds->sem_nsems = ds64->sem_nsems;

> +}

> +

> +static void

> +semid_ds_to_semid64_ds (struct __semid64_ds *ds64, const struct semid_ds *ds)

> +{

> +  ds64->sem_perm = ds->sem_perm;

> +  ds64->sem_otime = ds->sem_otime

> +		    | ((__time64_t) ds->__sem_otime_high << 32);

> +  ds64->sem_ctime = ds->sem_ctime

> +		    | ((__time64_t) ds->__sem_ctime_high << 32);

> +  ds64->sem_nsems = ds->sem_nsems;

> +}

> +

> +static union semun64

> +semun_to_semun64 (int cmd, union semun semun, struct __semid64_ds *semid64)

> +{

> +  union semun64 r = { 0 };

> +  switch (cmd)

> +    {

> +    case SETVAL:

> +      r.val = semun.val;

> +      break;

> +    case GETALL:

> +    case SETALL:

> +      r.array = semun.array;

> +      break;

> +    case IPC_STAT:

> +    case IPC_SET:

> +      r.buf = semid64;

> +      semid_ds_to_semid64_ds (r.buf, semun.buf);

> +# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T

> +      if (cmd == IPC_SET)

> +	r.buf->sem_perm.mode *= 0x10000U;

> +# endif

> +      break;

> +    case IPC_INFO:

> +    case SEM_INFO:

> +      r.__buf = semun.__buf;

> +      break;

> +    }

> +  return r;

> +}


OK.

> +

> +int

> +__semctl (int semid, int semnum, int cmd, ...)

> +{

> +  union semun arg = { 0 };

> +

> +  va_list ap;

> +

> +  /* Get the argument only if required.  */

> +  switch (cmd)

> +    {

> +    case SETVAL:        /* arg.val */

> +    case GETALL:        /* arg.array */

> +    case SETALL:

> +    case IPC_STAT:      /* arg.buf */

> +    case IPC_SET:

> +    case SEM_STAT:

> +    case IPC_INFO:      /* arg.__buf */

> +    case SEM_INFO:

> +      va_start (ap, cmd);

> +      arg = va_arg (ap, union semun);

> +      va_end (ap);

> +      break;

> +    }

> +

> +  struct __semid64_ds semid64;

> +  union semun64 arg64 = semun_to_semun64 (cmd, arg, &semid64);

> +

> +  int ret = __semctl64 (semid, semnum, cmd, arg64);


OK. Implement with __semctl64.

> +  if (ret < 0)

> +    return ret;

> +

> +  switch (cmd)

> +    {

> +    case IPC_STAT:

> +    case SEM_STAT:

> +    case SEM_STAT_ANY:

> +      semid64_ds_to_semid_ds (arg.buf, arg64.buf);

>      }

>  

>    return ret;

>  }

> -versioned_symbol (libc, __new_semctl, semctl, DEFAULT_VERSION);

> +#endif

> +

> +#ifndef DEFAULT_VERSION

> +# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T

> +#  define DEFAULT_VERSION GLIBC_2_2

> +# else

> +#  define DEFAULT_VERSION GLIBC_2_31

> +# endif

> +#endif

> +versioned_symbol (libc, __semctl, semctl, DEFAULT_VERSION);

>  

>  #if defined __ASSUME_SYSVIPC_BROKEN_MODE_T \

>      && SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_31)

> @@ -121,7 +304,7 @@ int

>  attribute_compat_text_section

>  __semctl_mode16 (int semid, int semnum, int cmd, ...)

>  {

> -  union semun arg = { 0 };

> +  semctl_arg_t arg = { 0 };

>    va_list ap;

>  

>    /* Get the argument only if required.  */

> @@ -136,7 +319,7 @@ __semctl_mode16 (int semid, int semnum, int cmd, ...)

>      case IPC_INFO:      /* arg.__buf */

>      case SEM_INFO:

>        va_start (ap, cmd);

> -      arg = va_arg (ap, union semun);

> +      arg = va_arg (ap, semctl_arg_t);

>        va_end (ap);

>        break;

>      }

> diff --git a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> index 46fcd79fb6..0110c1a940 100644

> --- a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>  #if __TIMESIZE == 32

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_otime;         /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;


OK.

>    __time_t sem_ctime;        /* last time changed by semctl() */

>  #else

>    __time_t sem_otime;         /* last semop() time */

> diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..8c4697f9ab

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_otime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_ctime;


OK. Matches sparc32.

> +  unsigned long sem_nsems;

> +  unsigned long __unused1;

> +  unsigned long __unused2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

> new file mode 100644

> index 0000000000..f9edf0f76f

> --- /dev/null

> +++ b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h

> @@ -0,0 +1,12 @@

> +/* Analogous to kernel struct semid64_ds used on semctl.  */

> +struct kernel_semid64_ds

> +{

> +  struct ipc_perm sem_perm;

> +  unsigned long sem_otime;

> +  unsigned long sem_otime_high;

> +  unsigned long sem_ctime;

> +  unsigned long sem_ctime_high;

> +  unsigned long sem_nsems;

> +  unsigned long __unused1;

> +  unsigned long __unused2;

> +};

> diff --git a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> index f7ec89d115..c3f2fde9fd 100644

> --- a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> +++ b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h

> @@ -25,9 +25,9 @@ struct semid_ds

>  {

>    struct ipc_perm sem_perm;   /* operation permission struct */

>    __time_t sem_otime;  /* last semop() time */

> -  __syscall_ulong_t __glibc_reserved1;

> +  __syscall_ulong_t __sem_otime_high;

>    __time_t sem_ctime;  /* last time changed by semctl() */

> -  __syscall_ulong_t __glibc_reserved2;

> +  __syscall_ulong_t __sem_ctime_high;

>    __syscall_ulong_t sem_nsems;    /* number of semaphores in set */

>    __syscall_ulong_t __glibc_reserved3;

>    __syscall_ulong_t __glibc_reserved4;

> 


OK.

-- 
Cheers,
Carlos.
Maciej W. Rozycki via Libc-alpha July 7, 2020, 2:09 p.m. | #3
On Tue, Jul 7, 2020 at 12:32 AM Carlos O'Donell <carlos@redhat.com> wrote:
>

> On 6/30/20 3:24 PM, Adhemerval Zanella via Libc-alpha wrote:

>

> OK for master with comment cleanups. Very clean, very easy to understand

> patch. I should finish the other 6 patches tomorrow morning.


Ack, I have included all your comment suggestions changes.

>

> No regressions on x86_64 or i686 (I did see the new rseq regression

> for posix/tst-affinity-static though).

>

> Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> Tested-by: Carlos O'Donell <carlos@redhat.com>


Thanks!

Patch

diff --git a/include/sys/sem.h b/include/sys/sem.h
index 69fdf1f752..a9151e057d 100644
--- a/include/sys/sem.h
+++ b/include/sys/sem.h
@@ -5,5 +5,12 @@ 
 
 __typeof__ (semtimedop) __semtimedop attribute_hidden;
 
+#if __TIMESIZE == 64
+# define __semctl64 __semctl
+#else
+extern int __semctl64 (int semid, int semnum, int cmd, ...);
+libc_hidden_proto (__semctl64);
+#endif
+
 # endif
 #endif
diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h
new file mode 100644
index 0000000000..bda9eb4469
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid64_ds.h
@@ -0,0 +1,33 @@ 
+/* Generic implementation of the semaphore struct semid64_ds.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_SEM_H
+# error "Never include <bits/types/struct_semid_ds.h> directly; use <sys/sem.h> instead."
+#endif
+
+#if __TIMESIZE == 64
+# define __semid64_ds semid_ds
+#else
+struct __semid64_ds
+{
+  struct ipc_perm sem_perm;		/* operation permission struct */
+  __time64_t sem_otime;			/* last semop() time */
+  __time64_t sem_ctime;			/* last time changed by semctl() */
+  __syscall_ulong_t sem_nsems;		/* number of semaphores in set */
+};
+#endif
diff --git a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h
index 4222e6a59f..bc26d8be08 100644
--- a/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/bits/types/struct_semid_ds.h
@@ -21,26 +21,19 @@ 
 #endif
 
 /* Data structure describing a set of semaphores.  */
-#if __TIMESIZE == 32
 struct semid_ds
 {
   struct ipc_perm sem_perm;        /* operation permission struct */
+#if __TIMESIZE == 32
   __time_t sem_otime;              /* last semop() time */
-  __syscall_ulong_t __glibc_reserved1;
+  __syscall_ulong_t __sem_otime_high;
   __time_t sem_ctime;             /* last time changed by semctl() */
-  __syscall_ulong_t __glibc_reserved2;
-  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */
-  __syscall_ulong_t __glibc_reserved3;
-  __syscall_ulong_t __glibc_reserved4;
-};
+  __syscall_ulong_t __sem_ctime_high;
 #else
-struct semid_ds
-{
-  struct ipc_perm sem_perm;		/* operation permission struct */
-  __time_t sem_otime;			/* last semop() time */
-  __time_t sem_ctime;			/* last time changed by semctl() */
-  __syscall_ulong_t sem_nsems;		/* number of semaphores in set */
+  __time_t sem_otime;
+  __time_t sem_ctime;
+#endif
+  __syscall_ulong_t sem_nsems;    /* number of semaphores in set */
   __syscall_ulong_t __glibc_reserved3;
   __syscall_ulong_t __glibc_reserved4;
 };
-#endif
diff --git a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h
index d4c50b5ef8..68f9eca24c 100644
--- a/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/hppa/bits/types/struct_semid_ds.h
@@ -21,16 +21,14 @@ 
 #endif
 
 /* Data structure describing a set of semaphores.  */
-#if __TIMESIZE == 32
 struct semid_ds
 {
   struct ipc_perm sem_perm;   /* operation permission struct */
-  __syscall_ulong_t __glibc_reserved1;
+  __syscall_ulong_t __sem_otime_high;
   __time_t sem_otime;         /* last semop() time */
-  __syscall_ulong_t __glibc_reserved2;
+  __syscall_ulong_t __sem_ctime_high;
   __time_t sem_ctime;         /* last time changed by semctl() */
   __syscall_ulong_t sem_nsems;    /* number of semaphores in set */
   __syscall_ulong_t __glibc_reserved3;
   __syscall_ulong_t __glibc_reserved4;
 };
-#endif
diff --git a/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..2871030d0d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/hppa/struct_kernel_semid64_ds.h
@@ -0,0 +1,12 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime_high;
+  unsigned long sem_otime;
+  unsigned long sem_ctime_high;
+  unsigned long sem_ctime;
+  unsigned long sem_nsems;
+  unsigned long __ununsed1;
+  unsigned long __ununsed2;
+};
diff --git a/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..bab9cf63ba
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/i386/struct_kernel_semid64_ds.h
@@ -0,0 +1,12 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime;
+  unsigned long sem_otime_high;
+  unsigned long sem_ctime;
+  unsigned long sem_ctime_high;
+  __syscall_ulong_t sem_nsems;
+  __syscall_ulong_t __unused3;
+  __syscall_ulong_t __unused4;
+};
diff --git a/sysdeps/unix/sysv/linux/ipc_priv.h b/sysdeps/unix/sysv/linux/ipc_priv.h
index 15a6e683a4..93a6e5cb24 100644
--- a/sysdeps/unix/sysv/linux/ipc_priv.h
+++ b/sysdeps/unix/sysv/linux/ipc_priv.h
@@ -53,4 +53,14 @@  struct __old_ipc_perm
 #define SEMTIMEDOP_IPC_ARGS(__nsops, __sops, __timeout) \
   (__nsops), 0, (__sops), (__timeout)
 
+/* Linux SysV ipc does not provide new syscalls for 64-bit time support on
+   32-bit architectures, but rather split the timestamps on previous unused
+   fields.  */
+#if (__WORDSIZE == 32 \
+     && (!defined __SYSCALL_WORDSIZE || __SYSCALL_WORDSIZE == 32))
+# define __IPC_TIME64 1
+#else
+# define __IPC_TIME64 0
+#endif
+
 #include <ipc_ops.h>
diff --git a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h
index 8954209a29..eec4a18cae 100644
--- a/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/mips/bits/types/struct_semid_ds.h
@@ -27,6 +27,6 @@  struct semid_ds
   __time_t sem_otime;	/* last semop() time */
   __time_t sem_ctime;	/* last time changed by semctl() */
   __syscall_ulong_t sem_nsems;		/* number of semaphores in set */
-  __syscall_ulong_t __glibc_reserved3;
-  __syscall_ulong_t __glibc_reserved4;
+  __syscall_ulong_t __sem_otime_high;
+  __syscall_ulong_t __sem_ctime_high;
 };
diff --git a/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..76a9d83ea5
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/mips/struct_kernel_semid64_ds.h
@@ -0,0 +1,10 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime;
+  unsigned long sem_ctime;
+  unsigned long sem_nsems;
+  unsigned long sem_otime_high;
+  unsigned long sem_ctime_high;
+};
diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h
index 300a9b98e9..d382d93c52 100644
--- a/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/powerpc/bits/types/struct_semid_ds.h
@@ -25,9 +25,9 @@  struct semid_ds
 {
   struct ipc_perm sem_perm;   /* operation permission struct */
 #if __TIMESIZE == 32
-  __syscall_ulong_t __glibc_reserved1;
+  __syscall_ulong_t __sem_otime_high;
   __time_t sem_otime;         /* last semop() time */
-  __syscall_ulong_t __glibc_reserved2;
+  __syscall_ulong_t __sem_ctime_high;
   __time_t sem_ctime;        /* last time changed by semctl() */
 #else
   __time_t sem_otime;         /* last semop() time */
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..7fa4ef6424
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/struct_kernel_semid64_ds.h
@@ -0,0 +1,12 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime_high;
+  unsigned long sem_otime;
+  unsigned long sem_ctime_high;
+  unsigned long sem_ctime;
+  unsigned long sem_nsems;
+  unsigned long __unused3;
+  unsigned long __unused4;
+};
diff --git a/sysdeps/unix/sysv/linux/semctl.c b/sysdeps/unix/sysv/linux/semctl.c
index 30571af49f..3a06270242 100644
--- a/sysdeps/unix/sysv/linux/semctl.c
+++ b/sysdeps/unix/sysv/linux/semctl.c
@@ -21,10 +21,13 @@ 
 #include <ipc_priv.h>
 #include <sysdep.h>
 #include <shlib-compat.h>
-#include <errno.h>
-#include <linux/posix_types.h>  /* For __kernel_mode_t.  */
+#include <bits/types/struct_semid64_ds.h>  /* For __semid64_ds.  */
+#include <linux/posix_types.h>             /* For __kernel_mode_t.  */
 
-/* Define a `union semun' suitable for Linux here.  */
+/* The struct used to issue the syscall.  For architecture that assume
+   64-bit time as default (!__ASSUME_TIME64_SYSCALLS) the syscall will
+   split the resulting 64-bit sem_{o,c}time in two fields (__sem_{o,c}time
+   and __sem_{o,c}time_hi).  */
 union semun
 {
   int val;			/* value for SETVAL */
@@ -33,16 +36,89 @@  union semun
   struct seminfo *__buf;	/* buffer for IPC_INFO */
 };
 
-#ifndef DEFAULT_VERSION
-# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T
-#  define DEFAULT_VERSION GLIBC_2_2
+#if __IPC_TIME64 == 0
+# define semun64 semun
+typedef union semun semctl_arg_t;
+#else
+# include <struct_kernel_semid64_ds.h>
+
+union ksemun64
+{
+  int val;
+  struct kernel_semid64_ds *buf;
+  unsigned short int *array;
+  struct seminfo *__buf;
+};
+
+# if __TIMESIZE == 64
+#  define semun64 semun
 # else
-#  define DEFAULT_VERSION GLIBC_2_31
+/* The struct used when __semctl64 is called.  */
+union semun64
+{
+  int val;
+  struct __semid64_ds *buf;
+  unsigned short int *array;
+  struct seminfo *__buf;
+};
 # endif
+
+static void
+semid64_to_ksemid64 (const struct __semid64_ds *semid64,
+		     struct kernel_semid64_ds *ksemid)
+{
+  ksemid->sem_perm       = semid64->sem_perm;
+  ksemid->sem_otime      = semid64->sem_otime;
+  ksemid->sem_otime_high = semid64->sem_otime >> 32;
+  ksemid->sem_ctime      = semid64->sem_ctime;
+  ksemid->sem_ctime_high = semid64->sem_ctime >> 32;
+  ksemid->sem_nsems      = semid64->sem_nsems;
+}
+
+static void
+ksemid64_to_semid64 (const struct kernel_semid64_ds *ksemid,
+		     struct __semid64_ds *semid64)
+{
+  semid64->sem_perm  = ksemid->sem_perm;
+  semid64->sem_otime = ksemid->sem_otime
+		       | ((__time64_t) ksemid->sem_otime_high << 32);
+  semid64->sem_ctime = ksemid->sem_ctime
+		       | ((__time64_t) ksemid->sem_ctime_high << 32);
+  semid64->sem_nsems = ksemid->sem_nsems;
+}
+
+static union ksemun64
+semun64_to_ksemun64 (int cmd, union semun64 semun64,
+		     struct kernel_semid64_ds *buf)
+{
+  union ksemun64 r = { 0 };
+  switch (cmd)
+    {
+    case SETVAL:
+      r.val = semun64.val;
+      break;
+    case GETALL:
+    case SETALL:
+      r.array = semun64.array;
+      break;
+    case IPC_STAT:
+    case IPC_SET:
+      r.buf = buf;
+      semid64_to_ksemid64 (semun64.buf, r.buf);
+      break;
+    case IPC_INFO:
+    case SEM_INFO:
+      r.__buf = semun64.__buf;
+      break;
+    }
+  return r;
+}
+
+typedef union ksemun64 semctl_arg_t;
 #endif
 
 static int
-semctl_syscall (int semid, int semnum, int cmd, union semun arg)
+semctl_syscall (int semid, int semnum, int cmd, semctl_arg_t arg)
 {
 #ifdef __ASSUME_DIRECT_SYSVIPC_SYSCALLS
   return INLINE_SYSCALL_CALL (semctl, semid, semnum, cmd | __IPC_64,
@@ -53,15 +129,15 @@  semctl_syscall (int semid, int semnum, int cmd, union semun arg)
 #endif
 }
 
+/* POSIX states ipc_perm mode should have type of mode_t.  */
+_Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)
+		== sizeof (mode_t),
+		"sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");
+
 int
-__new_semctl (int semid, int semnum, int cmd, ...)
+__semctl64 (int semid, int semnum, int cmd, ...)
 {
-  /* POSIX states ipc_perm mode should have type of mode_t.  */
-  _Static_assert (sizeof ((struct semid_ds){0}.sem_perm.mode)
-		  == sizeof (mode_t),
-		  "sizeof (msqid_ds.msg_perm.mode) != sizeof (mode_t)");
-
-  union semun arg = { 0 };
+  union semun64 arg64 = { 0 };
   va_list ap;
 
   /* Get the argument only if required.  */
@@ -76,44 +152,151 @@  __new_semctl (int semid, int semnum, int cmd, ...)
     case IPC_INFO:      /* arg.__buf */
     case SEM_INFO:
       va_start (ap, cmd);
-      arg = va_arg (ap, union semun);
+      arg64 = va_arg (ap, union semun64);
       va_end (ap);
       break;
     }
 
-#ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
-  struct semid_ds tmpds;
-  if (cmd == IPC_SET)
-    {
-      tmpds = *arg.buf;
-      tmpds.sem_perm.mode *= 0x10000U;
-      arg.buf = &tmpds;
-    }
+#if __IPC_TIME64
+  struct kernel_semid64_ds ksemid;
+  union ksemun64 ksemun = semun64_to_ksemun64 (cmd, arg64, &ksemid);
+  union ksemun64 arg = ksemun;
+#else
+  union semun arg = arg64;
 #endif
 
   int ret = semctl_syscall (semid, semnum, cmd, arg);
+  if (ret < 0)
+    return ret;
 
-  if (ret >= 0)
+  switch (cmd)
     {
-      switch (cmd)
-	{
-        case IPC_STAT:
-        case SEM_STAT:
-        case SEM_STAT_ANY:
+    case IPC_STAT:
+    case SEM_STAT:
+    case SEM_STAT_ANY:
 #ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
-          arg.buf->sem_perm.mode >>= 16;
+      arg.buf->sem_perm.mode >>= 16;
 #else
-	  /* Old Linux kernel versions might not clear the mode padding.  */
-	  if (sizeof ((struct semid_ds){0}.sem_perm.mode)
-	      != sizeof (__kernel_mode_t))
-	    arg.buf->sem_perm.mode &= 0xFFFF;
+      /* Old Linux kernel versions might not clear the mode padding.  */
+      if (sizeof ((struct semid_ds){0}.sem_perm.mode)
+	  != sizeof (__kernel_mode_t))
+	arg.buf->sem_perm.mode &= 0xFFFF;
 #endif
-	}
+
+#if __IPC_TIME64
+      ksemid64_to_semid64 (arg.buf, arg64.buf);
+#endif
+    }
+
+  return ret;
+}
+#if __TIMESIZE != 64
+libc_hidden_def (__semctl64)
+
+
+/* The 64-bit time_t semid_ds version might have a different layout and
+   internal field alignment.  */
+static void
+semid64_ds_to_semid_ds (struct semid_ds *ds, const struct __semid64_ds *ds64)
+{
+  ds->sem_perm = ds64->sem_perm;
+  ds->sem_otime = ds64->sem_otime;
+  ds->sem_ctime = ds64->sem_ctime;
+  ds->sem_nsems = ds64->sem_nsems;
+}
+
+static void
+semid_ds_to_semid64_ds (struct __semid64_ds *ds64, const struct semid_ds *ds)
+{
+  ds64->sem_perm = ds->sem_perm;
+  ds64->sem_otime = ds->sem_otime
+		    | ((__time64_t) ds->__sem_otime_high << 32);
+  ds64->sem_ctime = ds->sem_ctime
+		    | ((__time64_t) ds->__sem_ctime_high << 32);
+  ds64->sem_nsems = ds->sem_nsems;
+}
+
+static union semun64
+semun_to_semun64 (int cmd, union semun semun, struct __semid64_ds *semid64)
+{
+  union semun64 r = { 0 };
+  switch (cmd)
+    {
+    case SETVAL:
+      r.val = semun.val;
+      break;
+    case GETALL:
+    case SETALL:
+      r.array = semun.array;
+      break;
+    case IPC_STAT:
+    case IPC_SET:
+      r.buf = semid64;
+      semid_ds_to_semid64_ds (r.buf, semun.buf);
+# ifdef __ASSUME_SYSVIPC_BROKEN_MODE_T
+      if (cmd == IPC_SET)
+	r.buf->sem_perm.mode *= 0x10000U;
+# endif
+      break;
+    case IPC_INFO:
+    case SEM_INFO:
+      r.__buf = semun.__buf;
+      break;
+    }
+  return r;
+}
+
+int
+__semctl (int semid, int semnum, int cmd, ...)
+{
+  union semun arg = { 0 };
+
+  va_list ap;
+
+  /* Get the argument only if required.  */
+  switch (cmd)
+    {
+    case SETVAL:        /* arg.val */
+    case GETALL:        /* arg.array */
+    case SETALL:
+    case IPC_STAT:      /* arg.buf */
+    case IPC_SET:
+    case SEM_STAT:
+    case IPC_INFO:      /* arg.__buf */
+    case SEM_INFO:
+      va_start (ap, cmd);
+      arg = va_arg (ap, union semun);
+      va_end (ap);
+      break;
+    }
+
+  struct __semid64_ds semid64;
+  union semun64 arg64 = semun_to_semun64 (cmd, arg, &semid64);
+
+  int ret = __semctl64 (semid, semnum, cmd, arg64);
+  if (ret < 0)
+    return ret;
+
+  switch (cmd)
+    {
+    case IPC_STAT:
+    case SEM_STAT:
+    case SEM_STAT_ANY:
+      semid64_ds_to_semid_ds (arg.buf, arg64.buf);
     }
 
   return ret;
 }
-versioned_symbol (libc, __new_semctl, semctl, DEFAULT_VERSION);
+#endif
+
+#ifndef DEFAULT_VERSION
+# ifndef __ASSUME_SYSVIPC_BROKEN_MODE_T
+#  define DEFAULT_VERSION GLIBC_2_2
+# else
+#  define DEFAULT_VERSION GLIBC_2_31
+# endif
+#endif
+versioned_symbol (libc, __semctl, semctl, DEFAULT_VERSION);
 
 #if defined __ASSUME_SYSVIPC_BROKEN_MODE_T \
     && SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_31)
@@ -121,7 +304,7 @@  int
 attribute_compat_text_section
 __semctl_mode16 (int semid, int semnum, int cmd, ...)
 {
-  union semun arg = { 0 };
+  semctl_arg_t arg = { 0 };
   va_list ap;
 
   /* Get the argument only if required.  */
@@ -136,7 +319,7 @@  __semctl_mode16 (int semid, int semnum, int cmd, ...)
     case IPC_INFO:      /* arg.__buf */
     case SEM_INFO:
       va_start (ap, cmd);
-      arg = va_arg (ap, union semun);
+      arg = va_arg (ap, semctl_arg_t);
       va_end (ap);
       break;
     }
diff --git a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h
index 46fcd79fb6..0110c1a940 100644
--- a/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/sparc/bits/types/struct_semid_ds.h
@@ -25,9 +25,9 @@  struct semid_ds
 {
   struct ipc_perm sem_perm;   /* operation permission struct */
 #if __TIMESIZE == 32
-  __syscall_ulong_t __glibc_reserved1;
+  __syscall_ulong_t __sem_otime_high;
   __time_t sem_otime;         /* last semop() time */
-  __syscall_ulong_t __glibc_reserved2;
+  __syscall_ulong_t __sem_ctime_high;
   __time_t sem_ctime;        /* last time changed by semctl() */
 #else
   __time_t sem_otime;         /* last semop() time */
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..8c4697f9ab
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/struct_kernel_semid64_ds.h
@@ -0,0 +1,12 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime_high;
+  unsigned long sem_otime;
+  unsigned long sem_ctime_high;
+  unsigned long sem_ctime;
+  unsigned long sem_nsems;
+  unsigned long __unused1;
+  unsigned long __unused2;
+};
diff --git a/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h
new file mode 100644
index 0000000000..f9edf0f76f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/struct_kernel_semid64_ds.h
@@ -0,0 +1,12 @@ 
+/* Analogous to kernel struct semid64_ds used on semctl.  */
+struct kernel_semid64_ds
+{
+  struct ipc_perm sem_perm;
+  unsigned long sem_otime;
+  unsigned long sem_otime_high;
+  unsigned long sem_ctime;
+  unsigned long sem_ctime_high;
+  unsigned long sem_nsems;
+  unsigned long __unused1;
+  unsigned long __unused2;
+};
diff --git a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h
index f7ec89d115..c3f2fde9fd 100644
--- a/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h
+++ b/sysdeps/unix/sysv/linux/x86/bits/types/struct_semid_ds.h
@@ -25,9 +25,9 @@  struct semid_ds
 {
   struct ipc_perm sem_perm;   /* operation permission struct */
   __time_t sem_otime;  /* last semop() time */
-  __syscall_ulong_t __glibc_reserved1;
+  __syscall_ulong_t __sem_otime_high;
   __time_t sem_ctime;  /* last time changed by semctl() */
-  __syscall_ulong_t __glibc_reserved2;
+  __syscall_ulong_t __sem_ctime_high;
   __syscall_ulong_t sem_nsems;    /* number of semaphores in set */
   __syscall_ulong_t __glibc_reserved3;
   __syscall_ulong_t __glibc_reserved4;