include/uapi/asm-generic/sembuf.h

   1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
   2 #ifndef __ASM_GENERIC_SEMBUF_H
   3 #define __ASM_GENERIC_SEMBUF_H
   4
   5 #include <asm/bitsperlong.h>
   6
   7 /*
   8  * The semid64_ds structure for x86 architecture.
   9  * Note extra padding because this structure is passed back and forth
  10  * between kernel and user space.
  11  *
  12  * semid64_ds was originally meant to be architecture specific, but
  13  * everyone just ended up making identical copies without specific
  14  * optimizations, so we may just as well all use the same one.
  15  *
  16  * 64 bit architectures typically define a 64 bit __kernel_time_t,
  17  * so they do not need the first two padding words.
  18  * On big-endian systems, the padding is in the wrong place.
  19  *
  20  * Pad space is left for:
  21  * - 64-bit time_t to solve y2038 problem
  22  * - 2 miscellaneous 32-bit values
  23  */
  24 struct semid64_ds {
  25         struct ipc64_perm sem_perm;     /* permissions .. see ipc.h */
  26         __kernel_time_t sem_otime;      /* last semop time */
  27 #if __BITS_PER_LONG != 64
  28         unsigned long   __unused1;
  29 #endif
  30         __kernel_time_t sem_ctime;      /* last change time */
  31 #if __BITS_PER_LONG != 64
  32         unsigned long   __unused2;
  33 #endif
  34         unsigned long   sem_nsems;      /* no. of semaphores in array */
  35         unsigned long   __unused3;
  36         unsigned long   __unused4;
  37 };
  38
  39 #endif /* __ASM_GENERIC_SEMBUF_H */