include/linux/shm.h

   1 #ifndef _LINUX_SHM_H_
   2 #define _LINUX_SHM_H_
   3
   4 #include <linux/ipc.h>
   5
   6 #include <asm/shmparam.h>
   7
   8 struct shmid_ds {
   9         struct ipc_perm         shm_perm;       /* operation perms */
  10         int                     shm_segsz;      /* size of segment (bytes) */
  11         __kernel_time_t         shm_atime;      /* last attach time */
  12         __kernel_time_t         shm_dtime;      /* last detach time */
  13         __kernel_time_t         shm_ctime;      /* last change time */
  14         __kernel_ipc_pid_t      shm_cpid;       /* pid of creator */
  15         __kernel_ipc_pid_t      shm_lpid;       /* pid of last operator */
  16         unsigned short          shm_nattch;     /* no. of current attaches */
  17         /* the following are private */
  18         unsigned short          shm_npages;     /* size of segment (pages) */
  19         unsigned long           *shm_pages;     /* array of ptrs to frames -> SHMMAX */
  20         struct vm_area_struct   *attaches;      /* descriptors for attaches */
  21 };
  22
  23 /* permission flag for shmget */
  24 #define SHM_R           0400    /* or S_IRUGO from <linux/stat.h> */
  25 #define SHM_W           0200    /* or S_IWUGO from <linux/stat.h> */
  26
  27 /* mode for attach */
  28 #define SHM_RDONLY      010000  /* read-only access */
  29 #define SHM_RND         020000  /* round attach address to SHMLBA boundary */
  30 #define SHM_REMAP       040000  /* take-over region on attach */
  31
  32 /* super user shmctl commands */
  33 #define SHM_LOCK        11
  34 #define SHM_UNLOCK      12
  35
  36 /* ipcs ctl commands */
  37 #define SHM_STAT        13
  38 #define SHM_INFO        14
  39
  40 struct  shminfo {
  41         int shmmax;
  42         int shmmin;
  43         int shmmni;
  44         int shmseg;
  45         int shmall;
  46 };
  47
  48 struct shm_info {
  49         int used_ids;
  50         unsigned long shm_tot;  /* total allocated shm */
  51         unsigned long shm_rss;  /* total resident shm */
  52         unsigned long shm_swp;  /* total swapped shm */
  53         unsigned long swap_attempts;
  54         unsigned long swap_successes;
  55 };
  56
  57 #ifdef __KERNEL__
  58
  59 /* shm_mode upper byte flags */
  60 #define SHM_DEST        01000   /* segment will be destroyed on last detach */
  61 #define SHM_LOCKED      02000   /* segment will not be swapped */
  62
  63 asmlinkage int sys_shmget (key_t key, int size, int flag);
  64 asmlinkage int sys_shmat (int shmid, char *shmaddr, int shmflg, unsigned long *addr);
  65 asmlinkage int sys_shmdt (char *shmaddr);
  66 asmlinkage int sys_shmctl (int shmid, int cmd, struct shmid_ds *buf);
  67 extern void shm_unuse(unsigned long entry, unsigned long page);
  68
  69 #endif /* __KERNEL__ */
  70
  71 #endif /* _LINUX_SHM_H_ */