include/linux/ipc_namespace.h

   1 #ifndef __IPC_NAMESPACE_H__
   2 #define __IPC_NAMESPACE_H__
   3
   4 #include <linux/err.h>
   5 #include <linux/idr.h>
   6 #include <linux/rwsem.h>
   7
   8 struct ipc_ids {
   9         int in_use;
  10         unsigned short seq;
  11         unsigned short seq_max;
  12         struct rw_semaphore rw_mutex;
  13         struct idr ipcs_idr;
  14 };
  15
  16 struct ipc_namespace {
  17         struct kref     kref;
  18         struct ipc_ids  ids[3];
  19
  20         int             sem_ctls[4];
  21         int             used_sems;
  22
  23         int             msg_ctlmax;
  24         int             msg_ctlmnb;
  25         int             msg_ctlmni;
  26         atomic_t        msg_bytes;
  27         atomic_t        msg_hdrs;
  28
  29         size_t          shm_ctlmax;
  30         size_t          shm_ctlall;
  31         int             shm_ctlmni;
  32         int             shm_tot;
  33 };
  34
  35 extern struct ipc_namespace init_ipc_ns;
  36
  37 #ifdef CONFIG_SYSVIPC
  38 #define INIT_IPC_NS(ns)         .ns             = &init_ipc_ns,
  39 #else
  40 #define INIT_IPC_NS(ns)
  41 #endif
  42
  43 #if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
  44 extern void free_ipc_ns(struct kref *kref);
  45 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
  46                                                 struct ipc_namespace *ns);
  47
  48 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  49 {
  50         if (ns)
  51                 kref_get(&ns->kref);
  52         return ns;
  53 }
  54
  55 static inline void put_ipc_ns(struct ipc_namespace *ns)
  56 {
  57         kref_put(&ns->kref, free_ipc_ns);
  58 }
  59 #else
  60 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
  61                 struct ipc_namespace *ns)
  62 {
  63         if (flags & CLONE_NEWIPC)
  64                 return ERR_PTR(-EINVAL);
  65
  66         return ns;
  67 }
  68
  69 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  70 {
  71         return ns;
  72 }
  73
  74 static inline void put_ipc_ns(struct ipc_namespace *ns)
  75 {
  76 }
  77 #endif
  78 #endif