include/linux/ipc.h

   1 #ifndef _LINUX_IPC_H
   2 #define _LINUX_IPC_H
   3
   4 #include <linux/types.h>
   5
   6 #define IPC_PRIVATE ((__kernel_key_t) 0)
   7
   8 /* Obsolete, used only for backwards compatibility and libc5 compiles */
   9 struct ipc_perm
  10 {
  11         __kernel_key_t  key;
  12         __kernel_uid_t  uid;
  13         __kernel_gid_t  gid;
  14         __kernel_uid_t  cuid;
  15         __kernel_gid_t  cgid;
  16         __kernel_mode_t mode;
  17         unsigned short  seq;
  18 };
  19
  20 /* Include the definition of ipc64_perm */
  21 #include <asm/ipcbuf.h>
  22
  23 /* resource get request flags */
  24 #define IPC_CREAT  00001000   /* create if key is nonexistent */
  25 #define IPC_EXCL   00002000   /* fail if key exists */
  26 #define IPC_NOWAIT 00004000   /* return error on wait */
  27
  28 /* these fields are used by the DIPC package so the kernel as standard
  29    should avoid using them if possible */
  30
  31 #define IPC_DIPC 00010000  /* make it distributed */
  32 #define IPC_OWN  00020000  /* this machine is the DIPC owner */
  33
  34 /*
  35  * Control commands used with semctl, msgctl and shmctl
  36  * see also specific commands in sem.h, msg.h and shm.h
  37  */
  38 #define IPC_RMID 0     /* remove resource */
  39 #define IPC_SET  1     /* set ipc_perm options */
  40 #define IPC_STAT 2     /* get ipc_perm options */
  41 #define IPC_INFO 3     /* see ipcs */
  42
  43 /*
  44  * Version flags for semctl, msgctl, and shmctl commands
  45  * These are passed as bitflags or-ed with the actual command
  46  */
  47 #define IPC_OLD 0       /* Old version (no 32-bit UID support on many
  48                            architectures) */
  49 #define IPC_64  0x0100  /* New version (support 32-bit UIDs, bigger
  50                            message sizes, etc. */
  51
  52 /*
  53  * These are used to wrap system calls.
  54  *
  55  * See architecture code for ugly details..
  56  */
  57 struct ipc_kludge {
  58         struct msgbuf __user *msgp;
  59         long msgtyp;
  60 };
  61
  62 #define SEMOP            1
  63 #define SEMGET           2
  64 #define SEMCTL           3
  65 #define SEMTIMEDOP       4
  66 #define MSGSND          11
  67 #define MSGRCV          12
  68 #define MSGGET          13
  69 #define MSGCTL          14
  70 #define SHMAT           21
  71 #define SHMDT           22
  72 #define SHMGET          23
  73 #define SHMCTL          24
  74
  75 /* Used by the DIPC package, try and avoid reusing it */
  76 #define DIPC            25
  77
  78 #define IPCCALL(version,op)     ((version)<<16 | (op))
  79
  80 #ifdef __KERNEL__
  81
  82 #include <linux/kref.h>
  83 #include <linux/spinlock.h>
  84
  85 #define IPCMNI 32768  /* <= MAX_INT limit for ipc arrays (including sysctl changes) */
  86
  87 /* used by in-kernel data structures */
  88 struct kern_ipc_perm
  89 {
  90         spinlock_t      lock;
  91         int             deleted;
  92         int             id;
  93         key_t           key;
  94         uid_t           uid;
  95         gid_t           gid;
  96         uid_t           cuid;
  97         gid_t           cgid;
  98         mode_t          mode;
  99         unsigned long   seq;
 100         void            *security;
 101 };
 102
 103 struct ipc_ids;
 104 struct ipc_namespace {
 105         struct kref     kref;
 106         struct ipc_ids  *ids[3];
 107
 108         int             sem_ctls[4];
 109         int             used_sems;
 110
 111         int             msg_ctlmax;
 112         int             msg_ctlmnb;
 113         int             msg_ctlmni;
 114         atomic_t        msg_bytes;
 115         atomic_t        msg_hdrs;
 116
 117         size_t          shm_ctlmax;
 118         size_t          shm_ctlall;
 119         int             shm_ctlmni;
 120         int             shm_tot;
 121 };
 122
 123 extern struct ipc_namespace init_ipc_ns;
 124
 125 #ifdef CONFIG_SYSVIPC
 126 #define INIT_IPC_NS(ns)         .ns             = &init_ipc_ns,
 127 extern void free_ipc_ns(struct kref *kref);
 128 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
 129                                                 struct ipc_namespace *ns);
 130 #else
 131 #define INIT_IPC_NS(ns)
 132 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
 133                                                 struct ipc_namespace *ns)
 134 {
 135         return ns;
 136 }
 137 #endif
 138
 139 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
 140 {
 141 #ifdef CONFIG_SYSVIPC
 142         if (ns)
 143                 kref_get(&ns->kref);
 144 #endif
 145         return ns;
 146 }
 147
 148 static inline void put_ipc_ns(struct ipc_namespace *ns)
 149 {
 150 #ifdef CONFIG_SYSVIPC
 151         kref_put(&ns->kref, free_ipc_ns);
 152 #endif
 153 }
 154
 155 #endif /* __KERNEL__ */
 156
 157 #endif /* _LINUX_IPC_H */