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-rw-r--r--include/uapi/asm-generic/sembuf.h38
1 files changed, 38 insertions, 0 deletions
diff --git a/include/uapi/asm-generic/sembuf.h b/include/uapi/asm-generic/sembuf.h
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+++ b/include/uapi/asm-generic/sembuf.h
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+#ifndef __ASM_GENERIC_SEMBUF_H
+#define __ASM_GENERIC_SEMBUF_H
+
+#include <asm/bitsperlong.h>
+
+/*
+ * 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 typically define a 64 bit __kernel_time_t,
+ * so they do not need the first two padding words.
+ * On big-endian systems, the padding is in the wrong place.
+ *
+ * Pad space is left for:
+ * - 64-bit time_t to solve y2038 problem
+ * - 2 miscellaneous 32-bit values
+ */
+struct semid64_ds {
+ struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
+ __kernel_time_t sem_otime; /* last semop time */
+#if __BITS_PER_LONG != 64
+ unsigned long __unused1;
+#endif
+ __kernel_time_t sem_ctime; /* last change time */
+#if __BITS_PER_LONG != 64
+ unsigned long __unused2;
+#endif
+ unsigned long sem_nsems; /* no. of semaphores in array */
+ unsigned long __unused3;
+ unsigned long __unused4;
+};
+
+#endif /* __ASM_GENERIC_SEMBUF_H */