/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
 19struct 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
 27struct ipc_namespace {
 28	atomic_t	count;
 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	int		auto_msgmni;
 40
 41	size_t		shm_ctlmax;
 42	size_t		shm_ctlall;
 43	int		shm_ctlmni;
 44	int		shm_tot;
 45
 46	struct notifier_block ipcns_nb;
 47
 48	/* The kern_mount of the mqueuefs sb.  We take a ref on it */
 49	struct vfsmount	*mq_mnt;
 50
 51	/* # queues in this ns, protected by mq_lock */
 52	unsigned int    mq_queues_count;
 53
 54	/* next fields are set through sysctl */
 55	unsigned int    mq_queues_max;   /* initialized to DFLT_QUEUESMAX */
 56	unsigned int    mq_msg_max;      /* initialized to DFLT_MSGMAX */
 57	unsigned int    mq_msgsize_max;  /* initialized to DFLT_MSGSIZEMAX */
 58
 59};
 60
 61extern struct ipc_namespace init_ipc_ns;
 62extern atomic_t nr_ipc_ns;
 63
 64extern spinlock_t mq_lock;
 65
 66#ifdef CONFIG_SYSVIPC
 67extern int register_ipcns_notifier(struct ipc_namespace *);
 68extern int cond_register_ipcns_notifier(struct ipc_namespace *);
 69extern void unregister_ipcns_notifier(struct ipc_namespace *);
 70extern int ipcns_notify(unsigned long);
 71#else /* CONFIG_SYSVIPC */
 72static inline int register_ipcns_notifier(struct ipc_namespace *ns)
 73{ return 0; }
 74static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
 75{ return 0; }
 76static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
 77static inline int ipcns_notify(unsigned long l) { return 0; }
 78#endif /* CONFIG_SYSVIPC */
 79
 80#ifdef CONFIG_POSIX_MQUEUE
 81extern int mq_init_ns(struct ipc_namespace *ns);
 82/* default values */
 83#define DFLT_QUEUESMAX 256     /* max number of message queues */
 84#define DFLT_MSGMAX    10      /* max number of messages in each queue */
 85#define HARD_MSGMAX    (32768*sizeof(void *)/4)
 86#define DFLT_MSGSIZEMAX 8192   /* max message size */
 87#else
 88static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
 89#endif
 90
 91#if defined(CONFIG_IPC_NS)
 92extern struct ipc_namespace *copy_ipcs(unsigned long flags,
 93				       struct ipc_namespace *ns);
 94static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
 95{
 96	if (ns)
 97		atomic_inc(&ns->count);
 98	return ns;
 99}
100
101extern void put_ipc_ns(struct ipc_namespace *ns);
102#else
103static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
104		struct ipc_namespace *ns)
105{
106	if (flags & CLONE_NEWIPC)
107		return ERR_PTR(-EINVAL);
108
109	return ns;
110}
111
112static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
113{
114	return ns;
115}
116
117static inline void put_ipc_ns(struct ipc_namespace *ns)
118{
119}
120#endif
121
122#ifdef CONFIG_POSIX_MQUEUE_SYSCTL
123
124struct ctl_table_header;
125extern struct ctl_table_header *mq_register_sysctl_table(void);
126
127#else /* CONFIG_POSIX_MQUEUE_SYSCTL */
128
129static inline struct ctl_table_header *mq_register_sysctl_table(void)
130{
131	return NULL;
132}
133
134#endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
135#endif