aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/ipc.h
blob: 636094c29b167e185168d10882fd2c497903d166 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
#ifndef _LINUX_IPC_H
#define _LINUX_IPC_H

#include <linux/types.h>

#define IPC_PRIVATE ((__kernel_key_t) 0)  

/* Obsolete, used only for backwards compatibility and libc5 compiles */
struct ipc_perm
{
	__kernel_key_t	key;
	__kernel_uid_t	uid;
	__kernel_gid_t	gid;
	__kernel_uid_t	cuid;
	__kernel_gid_t	cgid;
	__kernel_mode_t	mode; 
	unsigned short	seq;
};

/* Include the definition of ipc64_perm */
#include <asm/ipcbuf.h>

/* resource get request flags */
#define IPC_CREAT  00001000   /* create if key is nonexistent */
#define IPC_EXCL   00002000   /* fail if key exists */
#define IPC_NOWAIT 00004000   /* return error on wait */

/* these fields are used by the DIPC package so the kernel as standard
   should avoid using them if possible */
   
#define IPC_DIPC 00010000  /* make it distributed */
#define IPC_OWN  00020000  /* this machine is the DIPC owner */

/* 
 * Control commands used with semctl, msgctl and shmctl 
 * see also specific commands in sem.h, msg.h and shm.h
 */
#define IPC_RMID 0     /* remove resource */
#define IPC_SET  1     /* set ipc_perm options */
#define IPC_STAT 2     /* get ipc_perm options */
#define IPC_INFO 3     /* see ipcs */

/*
 * Version flags for semctl, msgctl, and shmctl commands
 * These are passed as bitflags or-ed with the actual command
 */
#define IPC_OLD 0	/* Old version (no 32-bit UID support on many
			   architectures) */
#define IPC_64  0x0100  /* New version (support 32-bit UIDs, bigger
			   message sizes, etc. */

#ifdef __KERNEL__

#include <linux/kref.h>

#define IPCMNI 32768  /* <= MAX_INT limit for ipc arrays (including sysctl changes) */

/* used by in-kernel data structures */
struct kern_ipc_perm
{
	spinlock_t	lock;
	int		deleted;
	key_t		key;
	uid_t		uid;
	gid_t		gid;
	uid_t		cuid;
	gid_t		cgid;
	mode_t		mode; 
	unsigned long	seq;
	void		*security;
};

struct ipc_ids;
struct ipc_namespace {
	struct kref	kref;
	struct ipc_ids	*ids[3];

	int		sem_ctls[4];
	int		used_sems;

	int		msg_ctlmax;
	int		msg_ctlmnb;
	int		msg_ctlmni;

	size_t		shm_ctlmax;
	size_t		shm_ctlall;
	int		shm_ctlmni;
	int		shm_tot;
};

extern struct ipc_namespace init_ipc_ns;

#ifdef CONFIG_SYSVIPC
#define INIT_IPC_NS(ns)		.ns		= &init_ipc_ns,
#else
#define INIT_IPC_NS(ns)
#endif

#ifdef CONFIG_IPC_NS
extern void free_ipc_ns(struct kref *kref);
extern int copy_ipcs(unsigned long flags, struct task_struct *tsk);
extern int unshare_ipcs(unsigned long flags, struct ipc_namespace **ns);
#else
static inline int copy_ipcs(unsigned long flags, struct task_struct *tsk)
{
	return 0;
}
#endif

static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
#ifdef CONFIG_IPC_NS
	if (ns)
		kref_get(&ns->kref);
#endif
	return ns;
}

static inline void put_ipc_ns(struct ipc_namespace *ns)
{
#ifdef CONFIG_IPC_NS
	kref_put(&ns->kref, free_ipc_ns);
#endif
}

#endif /* __KERNEL__ */

#endif /* _LINUX_IPC_H */