From fc00c656c96528112d05cf0edf8631bd5eaea446 Mon Sep 17 00:00:00 2001 From: Kacper Date: Sun, 7 Dec 2025 20:10:31 +0100 Subject: Add build system scaffolding and libc headers --- include/arch/x86_64/asm-generic/sembuf.h | 45 ++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 include/arch/x86_64/asm-generic/sembuf.h (limited to 'include/arch/x86_64/asm-generic/sembuf.h') diff --git a/include/arch/x86_64/asm-generic/sembuf.h b/include/arch/x86_64/asm-generic/sembuf.h new file mode 100644 index 00000000..c6b036e1 --- /dev/null +++ b/include/arch/x86_64/asm-generic/sembuf.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef __ASM_GENERIC_SEMBUF_H +#define __ASM_GENERIC_SEMBUF_H + +#include +#include + +/* + * The semid64_ds structure for most architectures (though it came from x86_32 + * originally). 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 long time field here, while + * 32 bit architectures have a pair of unsigned long values. + * + * 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 + long sem_otime; /* last semop time */ + long 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 */ -- cgit v1.2.3