1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef __ASM_GENERIC_SHMBUF_H 3 #define __ASM_GENERIC_SHMBUF_H 4 5 #include <asm/bitsperlong.h> 6 7 /* 8 * The shmid64_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 * shmid64_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 * 21 * Pad space is left for: 22 * - 64-bit time_t to solve y2038 problem 23 * - 2 miscellaneous 32-bit values 24 */ 25 26 struct shmid64_ds { 27 struct ipc64_perm shm_perm; /* operation perms */ 28 size_t shm_segsz; /* size of segment (bytes) */ 29 __kernel_time_t shm_atime; /* last attach time */ 30 #if __BITS_PER_LONG != 64 31 unsigned long __unused1; 32 #endif 33 __kernel_time_t shm_dtime; /* last detach time */ 34 #if __BITS_PER_LONG != 64 35 unsigned long __unused2; 36 #endif 37 __kernel_time_t shm_ctime; /* last change time */ 38 #if __BITS_PER_LONG != 64 39 unsigned long __unused3; 40 #endif 41 __kernel_pid_t shm_cpid; /* pid of creator */ 42 __kernel_pid_t shm_lpid; /* pid of last operator */ 43 __kernel_ulong_t shm_nattch; /* no. of current attaches */ 44 __kernel_ulong_t __unused4; 45 __kernel_ulong_t __unused5; 46 }; 47 48 struct shminfo64 { 49 __kernel_ulong_t shmmax; 50 __kernel_ulong_t shmmin; 51 __kernel_ulong_t shmmni; 52 __kernel_ulong_t shmseg; 53 __kernel_ulong_t shmall; 54 __kernel_ulong_t __unused1; 55 __kernel_ulong_t __unused2; 56 __kernel_ulong_t __unused3; 57 __kernel_ulong_t __unused4; 58 }; 59 60 #endif /* __ASM_GENERIC_SHMBUF_H */ 61
