LXR linux/include/uapi/linux/shm.h

   1#ifndef _UAPI_LINUX_SHM_H_
   2#define _UAPI_LINUX_SHM_H_
   3
   4#include <linux/ipc.h>
   5#include <linux/errno.h>
   6#ifndef __KERNEL__
   7#include <unistd.h>
   8#endif
   9
  10/*
  11 * SHMMAX, SHMMNI and SHMALL are upper limits are defaults which can
  12 * be increased by sysctl
  13 */
  14
  15#define SHMMAX 0x2000000                 /* max shared seg size (bytes) */
  16#define SHMMIN 1                         /* min shared seg size (bytes) */
  17#define SHMMNI 4096                      /* max num of segs system wide */
  18#ifndef __KERNEL__
  19#define SHMALL (SHMMAX/getpagesize()*(SHMMNI/16))
  20#endif
  21#define SHMSEG SHMMNI                    /* max shared segs per process */
  22
  23
  24/* Obsolete, used only for backwards compatibility and libc5 compiles */
  25struct shmid_ds {
  26        struct ipc_perm         shm_perm;       /* operation perms */
  27        int                     shm_segsz;      /* size of segment (bytes) */
  28        __kernel_time_t         shm_atime;      /* last attach time */
  29        __kernel_time_t         shm_dtime;      /* last detach time */
  30        __kernel_time_t         shm_ctime;      /* last change time */
  31        __kernel_ipc_pid_t      shm_cpid;       /* pid of creator */
  32        __kernel_ipc_pid_t      shm_lpid;       /* pid of last operator */
  33        unsigned short          shm_nattch;     /* no. of current attaches */
  34        unsigned short          shm_unused;     /* compatibility */
  35        void                    *shm_unused2;   /* ditto - used by DIPC */
  36        void                    *shm_unused3;   /* unused */
  37};
  38
  39/* Include the definition of shmid64_ds and shminfo64 */
  40#include <asm/shmbuf.h>
  41
  42/* permission flag for shmget */
  43#define SHM_R           0400    /* or S_IRUGO from <linux/stat.h> */
  44#define SHM_W           0200    /* or S_IWUGO from <linux/stat.h> */
  45
  46/* mode for attach */
  47#define SHM_RDONLY      010000  /* read-only access */
  48#define SHM_RND         020000  /* round attach address to SHMLBA boundary */
  49#define SHM_REMAP       040000  /* take-over region on attach */
  50#define SHM_EXEC        0100000 /* execution access */
  51
  52/* super user shmctl commands */
  53#define SHM_LOCK        11
  54#define SHM_UNLOCK      12
  55
  56/* ipcs ctl commands */
  57#define SHM_STAT        13
  58#define SHM_INFO        14
  59
  60/* Obsolete, used only for backwards compatibility */
  61struct  shminfo {
  62        int shmmax;
  63        int shmmin;
  64        int shmmni;
  65        int shmseg;
  66        int shmall;
  67};
  68
  69struct shm_info {
  70        int used_ids;
  71        unsigned long shm_tot;  /* total allocated shm */
  72        unsigned long shm_rss;  /* total resident shm */
  73        unsigned long shm_swp;  /* total swapped shm */
  74        unsigned long swap_attempts;
  75        unsigned long swap_successes;
  76};
  77
  78
  79#endif /* _UAPI_LINUX_SHM_H_ */
  80