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         unsigned short          shm_unused;     /* compatibility */
  18         void                    *shm_unused2;   /* ditto - used by DIPC */
  19         void                    *shm_unused3;   /* unused */
  20 };
  21
  22 struct shmid_kernel
  23 {
  24         struct shmid_ds         u;
  25         /* the following are private */
  26         unsigned long           shm_npages;     /* size of segment (pages) */
  27         unsigned long           *shm_pages;     /* array of ptrs to frames -> SHMMAX */
  28         struct vm_area_struct   *attaches;      /* descriptors for attaches */
  29 };
  30
  31 /* permission flag for shmget */
  32 #define SHM_R           0400    /* or S_IRUGO from <linux/stat.h> */
  33 #define SHM_W           0200    /* or S_IWUGO from <linux/stat.h> */
  34
  35 /* mode for attach */
  36 #define SHM_RDONLY      010000  /* read-only access */
  37 #define SHM_RND         020000  /* round attach address to SHMLBA boundary */
  38 #define SHM_REMAP       040000  /* take-over region on attach */
  39
  40 /* super user shmctl commands */
  41 #define SHM_LOCK        11
  42 #define SHM_UNLOCK      12
  43
  44 /* ipcs ctl commands */
  45 #define SHM_STAT        13
  46 #define SHM_INFO        14
  47
  48 struct  shminfo {
  49         int shmmax;
  50         int shmmin;
  51         int shmmni;
  52         int shmseg;
  53         int shmall;
  54 };
  55
  56 struct shm_info {
  57         int used_ids;
  58         unsigned long shm_tot;  /* total allocated shm */
  59         unsigned long shm_rss;  /* total resident shm */
  60         unsigned long shm_swp;  /* total swapped shm */
  61         unsigned long swap_attempts;
  62         unsigned long swap_successes;
  63 };
  64
  65 #ifdef __KERNEL__
  66
  67 /* shm_mode upper byte flags */
  68 #define SHM_DEST        01000   /* segment will be destroyed on last detach */
  69 #define SHM_LOCKED      02000   /* segment will not be swapped */
  70
  71 asmlinkage int sys_shmget (key_t key, int size, int flag);
  72 asmlinkage int sys_shmat (int shmid, char *shmaddr, int shmflg, unsigned long *addr);
  73 asmlinkage int sys_shmdt (char *shmaddr);
  74 asmlinkage int sys_shmctl (int shmid, int cmd, struct shmid_ds *buf);
  75 extern void shm_unuse(unsigned long entry, unsigned long page);
  76
  77 #endif /* __KERNEL__ */
  78
  79 #endif /* _LINUX_SHM_H_ */