Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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#include <linux/nsproxy.h>
9
10/*
11 * ipc namespace events
12 */
13#define IPCNS_MEMCHANGED 0x00000001 /* Notify lowmem size changed */
14#define IPCNS_CREATED 0x00000002 /* Notify new ipc namespace created */
15#define IPCNS_REMOVED 0x00000003 /* Notify ipc namespace removed */
16
17#define IPCNS_CALLBACK_PRI 0
18
19struct user_namespace;
20
21struct ipc_ids {
22 int in_use;
23 unsigned short seq;
24 unsigned short seq_max;
25 struct rw_semaphore rw_mutex;
26 struct idr ipcs_idr;
27};
28
29struct ipc_namespace {
30 atomic_t count;
31 struct ipc_ids ids[3];
32
33 int sem_ctls[4];
34 int used_sems;
35
36 int msg_ctlmax;
37 int msg_ctlmnb;
38 int msg_ctlmni;
39 atomic_t msg_bytes;
40 atomic_t msg_hdrs;
41 int auto_msgmni;
42
43 size_t shm_ctlmax;
44 size_t shm_ctlall;
45 int shm_ctlmni;
46 int shm_tot;
47 /*
48 * Defines whether IPC_RMID is forced for _all_ shm segments regardless
49 * of shmctl()
50 */
51 int shm_rmid_forced;
52
53 struct notifier_block ipcns_nb;
54
55 /* The kern_mount of the mqueuefs sb. We take a ref on it */
56 struct vfsmount *mq_mnt;
57
58 /* # queues in this ns, protected by mq_lock */
59 unsigned int mq_queues_count;
60
61 /* next fields are set through sysctl */
62 unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */
63 unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */
64 unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */
65 unsigned int mq_msg_default;
66 unsigned int mq_msgsize_default;
67
68 /* user_ns which owns the ipc ns */
69 struct user_namespace *user_ns;
70};
71
72extern struct ipc_namespace init_ipc_ns;
73extern atomic_t nr_ipc_ns;
74
75extern spinlock_t mq_lock;
76
77#ifdef CONFIG_SYSVIPC
78extern int register_ipcns_notifier(struct ipc_namespace *);
79extern int cond_register_ipcns_notifier(struct ipc_namespace *);
80extern void unregister_ipcns_notifier(struct ipc_namespace *);
81extern int ipcns_notify(unsigned long);
82extern void shm_destroy_orphaned(struct ipc_namespace *ns);
83#else /* CONFIG_SYSVIPC */
84static inline int register_ipcns_notifier(struct ipc_namespace *ns)
85{ return 0; }
86static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
87{ return 0; }
88static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
89static inline int ipcns_notify(unsigned long l) { return 0; }
90static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
91#endif /* CONFIG_SYSVIPC */
92
93#ifdef CONFIG_POSIX_MQUEUE
94extern int mq_init_ns(struct ipc_namespace *ns);
95/*
96 * POSIX Message Queue default values:
97 *
98 * MIN_*: Lowest value an admin can set the maximum unprivileged limit to
99 * DFLT_*MAX: Default values for the maximum unprivileged limits
100 * DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
101 * an attribute to the open call and the queue must be created
102 * HARD_*: Highest value the maximums can be set to. These are enforced
103 * on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
104 * suitably high)
105 *
106 * POSIX Requirements:
107 * Per app minimum openable message queues - 8. This does not map well
108 * to the fact that we limit the number of queues on a per namespace
109 * basis instead of a per app basis. So, make the default high enough
110 * that no given app should have a hard time opening 8 queues.
111 * Minimum maximum for HARD_MSGMAX - 32767. I bumped this to 65536.
112 * Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this. However,
113 * we have run into a situation where running applications in the wild
114 * require this to be at least 5MB, and preferably 10MB, so I set the
115 * value to 16MB in hopes that this user is the worst of the bunch and
116 * the new maximum will handle anyone else. I may have to revisit this
117 * in the future.
118 */
119#define MIN_QUEUESMAX 1
120#define DFLT_QUEUESMAX 256
121#define HARD_QUEUESMAX 1024
122#define MIN_MSGMAX 1
123#define DFLT_MSG 10U
124#define DFLT_MSGMAX 10
125#define HARD_MSGMAX 65536
126#define MIN_MSGSIZEMAX 128
127#define DFLT_MSGSIZE 8192U
128#define DFLT_MSGSIZEMAX 8192
129#define HARD_MSGSIZEMAX (16*1024*1024)
130#else
131static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
132#endif
133
134#if defined(CONFIG_IPC_NS)
135extern struct ipc_namespace *copy_ipcs(unsigned long flags,
136 struct task_struct *tsk);
137static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
138{
139 if (ns)
140 atomic_inc(&ns->count);
141 return ns;
142}
143
144extern void put_ipc_ns(struct ipc_namespace *ns);
145#else
146static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
147 struct task_struct *tsk)
148{
149 if (flags & CLONE_NEWIPC)
150 return ERR_PTR(-EINVAL);
151
152 return tsk->nsproxy->ipc_ns;
153}
154
155static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
156{
157 return ns;
158}
159
160static inline void put_ipc_ns(struct ipc_namespace *ns)
161{
162}
163#endif
164
165#ifdef CONFIG_POSIX_MQUEUE_SYSCTL
166
167struct ctl_table_header;
168extern struct ctl_table_header *mq_register_sysctl_table(void);
169
170#else /* CONFIG_POSIX_MQUEUE_SYSCTL */
171
172static inline struct ctl_table_header *mq_register_sysctl_table(void)
173{
174 return NULL;
175}
176
177#endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
178#endif