include/uapi/asm-generic/shmbuf.h

   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 #include <asm/ipcbuf.h>
   7 #include <asm/posix_types.h>
   8
   9 /*
  10  * The shmid64_ds structure for x86 architecture.
  11  * Note extra padding because this structure is passed back and forth
  12  * between kernel and user space.
  13  *
  14  * shmid64_ds was originally meant to be architecture specific, but
  15  * everyone just ended up making identical copies without specific
  16  * optimizations, so we may just as well all use the same one.
  17  *
  18  * 64 bit architectures use a 64-bit long time field here, while
  19  * 32 bit architectures have a pair of unsigned long values.
  20  * On big-endian systems, the lower half is in the wrong place.
  21  *
  22  *
  23  * Pad space is left for:
  24  * - 2 miscellaneous 32-bit values
  25  */
  26
  27 struct shmid64_ds {
  28         struct ipc64_perm       shm_perm;       /* operation perms */
  29         __kernel_size_t         shm_segsz;      /* size of segment (bytes) */
  30 #if __BITS_PER_LONG == 64
  31         long                    shm_atime;      /* last attach time */
  32         long                    shm_dtime;      /* last detach time */
  33         long                    shm_ctime;      /* last change time */
  34 #else
  35         unsigned long           shm_atime;      /* last attach time */
  36         unsigned long           shm_atime_high;
  37         unsigned long           shm_dtime;      /* last detach time */
  38         unsigned long           shm_dtime_high;
  39         unsigned long           shm_ctime;      /* last change time */
  40         unsigned long           shm_ctime_high;
  41 #endif
  42         __kernel_pid_t          shm_cpid;       /* pid of creator */
  43         __kernel_pid_t          shm_lpid;       /* pid of last operator */
  44         unsigned long           shm_nattch;     /* no. of current attaches */
  45         unsigned long           __unused4;
  46         unsigned long           __unused5;
  47 };
  48
  49 struct shminfo64 {
  50         unsigned long           shmmax;
  51         unsigned long           shmmin;
  52         unsigned long           shmmni;
  53         unsigned long           shmseg;
  54         unsigned long           shmall;
  55         unsigned long           __unused1;
  56         unsigned long           __unused2;
  57         unsigned long           __unused3;
  58         unsigned long           __unused4;
  59 };
  60
  61 #endif /* __ASM_GENERIC_SHMBUF_H */