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 extern atomic_t nr_ipc_ns;
  37
  38 #ifdef CONFIG_SYSVIPC
  39 #define INIT_IPC_NS(ns)         .ns             = &init_ipc_ns,
  40 #else
  41 #define INIT_IPC_NS(ns)
  42 #endif
  43
  44 #if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
  45 extern void free_ipc_ns(struct kref *kref);
  46 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
  47                                        struct ipc_namespace *ns);
  48 extern void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
  49                       void (*free)(struct ipc_namespace *,
  50                                    struct kern_ipc_perm *));
  51
  52 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  53 {
  54         if (ns)
  55                 kref_get(&ns->kref);
  56         return ns;
  57 }
  58
  59 static inline void put_ipc_ns(struct ipc_namespace *ns)
  60 {
  61         kref_put(&ns->kref, free_ipc_ns);
  62 }
  63 #else
  64 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
  65                 struct ipc_namespace *ns)
  66 {
  67         if (flags & CLONE_NEWIPC)
  68                 return ERR_PTR(-EINVAL);
  69
  70         return ns;
  71 }
  72
  73 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  74 {
  75         return ns;
  76 }
  77
  78 static inline void put_ipc_ns(struct ipc_namespace *ns)
  79 {
  80 }
  81 #endif
  82 #endif