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 #ifdef __KERNEL__
  53
  54 #include <linux/kref.h>
  55 #include <linux/spinlock.h>
  56
  57 #define IPCMNI 32768  /* <= MAX_INT limit for ipc arrays (including sysctl changes) */
  58
  59 /* used by in-kernel data structures */
  60 struct kern_ipc_perm
  61 {
  62         spinlock_t      lock;
  63         int             deleted;
  64         key_t           key;
  65         uid_t           uid;
  66         gid_t           gid;
  67         uid_t           cuid;
  68         gid_t           cgid;
  69         mode_t          mode;
  70         unsigned long   seq;
  71         void            *security;
  72 };
  73
  74 struct ipc_ids;
  75 struct ipc_namespace {
  76         struct kref     kref;
  77         struct ipc_ids  *ids[3];
  78
  79         int             sem_ctls[4];
  80         int             used_sems;
  81
  82         int             msg_ctlmax;
  83         int             msg_ctlmnb;
  84         int             msg_ctlmni;
  85
  86         size_t          shm_ctlmax;
  87         size_t          shm_ctlall;
  88         int             shm_ctlmni;
  89         int             shm_tot;
  90 };
  91
  92 extern struct ipc_namespace init_ipc_ns;
  93
  94 #ifdef CONFIG_SYSVIPC
  95 #define INIT_IPC_NS(ns)         .ns             = &init_ipc_ns,
  96 extern void free_ipc_ns(struct kref *kref);
  97 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
  98                                                 struct ipc_namespace *ns);
  99 #else
 100 #define INIT_IPC_NS(ns)
 101 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
 102                                                 struct ipc_namespace *ns)
 103 {
 104         return ns;
 105 }
 106 #endif
 107
 108 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
 109 {
 110 #ifdef CONFIG_SYSVIPC
 111         if (ns)
 112                 kref_get(&ns->kref);
 113 #endif
 114         return ns;
 115 }
 116
 117 static inline void put_ipc_ns(struct ipc_namespace *ns)
 118 {
 119 #ifdef CONFIG_SYSVIPC
 120         kref_put(&ns->kref, free_ipc_ns);
 121 #endif
 122 }
 123
 124 #endif /* __KERNEL__ */
 125
 126 #endif /* _LINUX_IPC_H */