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 #include <linux/notifier.h>
   8
   9 /*
  10  * ipc namespace events
  11  */
  12 #define IPCNS_MEMCHANGED   0x00000001   /* Notify lowmem size changed */
  13 #define IPCNS_CREATED  0x00000002   /* Notify new ipc namespace created */
  14 #define IPCNS_REMOVED  0x00000003   /* Notify ipc namespace removed */
  15
  16 #define IPCNS_CALLBACK_PRI 0
  17
  18
  19 struct ipc_ids {
  20         int in_use;
  21         unsigned short seq;
  22         unsigned short seq_max;
  23         struct rw_semaphore rw_mutex;
  24         struct idr ipcs_idr;
  25 };
  26
  27 struct ipc_namespace {
  28         struct kref     kref;
  29         struct ipc_ids  ids[3];
  30
  31         int             sem_ctls[4];
  32         int             used_sems;
  33
  34         int             msg_ctlmax;
  35         int             msg_ctlmnb;
  36         int             msg_ctlmni;
  37         atomic_t        msg_bytes;
  38         atomic_t        msg_hdrs;
  39
  40         size_t          shm_ctlmax;
  41         size_t          shm_ctlall;
  42         int             shm_ctlmni;
  43         int             shm_tot;
  44
  45         struct notifier_block ipcns_nb;
  46 };
  47
  48 extern struct ipc_namespace init_ipc_ns;
  49 extern atomic_t nr_ipc_ns;
  50
  51 #ifdef CONFIG_SYSVIPC
  52 #define INIT_IPC_NS(ns)         .ns             = &init_ipc_ns,
  53
  54 extern int register_ipcns_notifier(struct ipc_namespace *);
  55 extern int unregister_ipcns_notifier(struct ipc_namespace *);
  56 extern int ipcns_notify(unsigned long);
  57
  58 #else /* CONFIG_SYSVIPC */
  59 #define INIT_IPC_NS(ns)
  60 #endif /* CONFIG_SYSVIPC */
  61
  62 #if defined(CONFIG_SYSVIPC) && defined(CONFIG_IPC_NS)
  63 extern void free_ipc_ns(struct kref *kref);
  64 extern struct ipc_namespace *copy_ipcs(unsigned long flags,
  65                                        struct ipc_namespace *ns);
  66 extern void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
  67                       void (*free)(struct ipc_namespace *,
  68                                    struct kern_ipc_perm *));
  69
  70 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  71 {
  72         if (ns)
  73                 kref_get(&ns->kref);
  74         return ns;
  75 }
  76
  77 static inline void put_ipc_ns(struct ipc_namespace *ns)
  78 {
  79         kref_put(&ns->kref, free_ipc_ns);
  80 }
  81 #else
  82 static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
  83                 struct ipc_namespace *ns)
  84 {
  85         if (flags & CLONE_NEWIPC)
  86                 return ERR_PTR(-EINVAL);
  87
  88         return ns;
  89 }
  90
  91 static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
  92 {
  93         return ns;
  94 }
  95
  96 static inline void put_ipc_ns(struct ipc_namespace *ns)
  97 {
  98 }
  99 #endif
 100 #endif