/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef __ASM_GENERIC_SEMBUF_H #define __ASM_GENERIC_SEMBUF_H #include /* * The semid64_ds structure for x86 architecture. * Note extra padding because this structure is passed back and forth * between kernel and user space. * * semid64_ds was originally meant to be architecture specific, but * everyone just ended up making identical copies without specific * optimizations, so we may just as well all use the same one. * * 64 bit architectures use a 64-bit __kernel_time_t here, while * 32 bit architectures have a pair of unsigned long values. * so they do not need the first two padding words. * * On big-endian systems, the padding is in the wrong place for * historic reasons, so user space has to reconstruct a time_t * value using * * user_semid_ds.sem_otime = kernel_semid64_ds.sem_otime + * ((long long)kernel_semid64_ds.sem_otime_high << 32) * * Pad space is left for 2 miscellaneous 32-bit values */ struct semid64_ds { struct ipc64_perm sem_perm; /* permissions .. see ipc.h */ #if __BITS_PER_LONG == 64 __kernel_time_t sem_otime; /* last semop time */ __kernel_time_t sem_ctime; /* last change time */ #else unsigned long sem_otime; /* last semop time */ unsigned long sem_otime_high; unsigned long sem_ctime; /* last change time */ unsigned long sem_ctime_high; #endif unsigned long sem_nsems; /* no. of semaphores in array */ unsigned long __unused3; unsigned long __unused4; }; #endif /* __ASM_GENERIC_SEMBUF_H */