1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef __ASM_GENERIC_MSGBUF_H 3 #define __ASM_GENERIC_MSGBUF_H 4 5 #include <asm/bitsperlong.h> 6 /* 7 * generic msqid64_ds structure. 8 * 9 * Note extra padding because this structure is passed back and forth 10 * between kernel and user space. 11 * 12 * msqid64_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 three 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 25 struct msqid64_ds { 26 struct ipc64_perm msg_perm; 27 __kernel_time_t msg_stime; /* last msgsnd time */ 28 #if __BITS_PER_LONG != 64 29 unsigned long __unused1; 30 #endif 31 __kernel_time_t msg_rtime; /* last msgrcv time */ 32 #if __BITS_PER_LONG != 64 33 unsigned long __unused2; 34 #endif 35 __kernel_time_t msg_ctime; /* last change time */ 36 #if __BITS_PER_LONG != 64 37 unsigned long __unused3; 38 #endif 39 __kernel_ulong_t msg_cbytes; /* current number of bytes on queue */ 40 __kernel_ulong_t msg_qnum; /* number of messages in queue */ 41 __kernel_ulong_t msg_qbytes; /* max number of bytes on queue */ 42 __kernel_pid_t msg_lspid; /* pid of last msgsnd */ 43 __kernel_pid_t msg_lrpid; /* last receive pid */ 44 __kernel_ulong_t __unused4; 45 __kernel_ulong_t __unused5; 46 }; 47 48 #endif /* __ASM_GENERIC_MSGBUF_H */ 49