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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_SHM_H_
2#define _LINUX_SHM_H_
3
4#include <linux/ipc.h>
5#include <linux/errno.h>
6#include <asm/page.h>
7
8/*
9 * SHMMAX, SHMMNI and SHMALL are upper limits are defaults which can
10 * be increased by sysctl
11 */
12
13#define SHMMAX 0x2000000 /* max shared seg size (bytes) */
14#define SHMMIN 1 /* min shared seg size (bytes) */
15#define SHMMNI 4096 /* max num of segs system wide */
16#define SHMALL (SHMMAX/PAGE_SIZE*(SHMMNI/16)) /* max shm system wide (pages) */
17#define SHMSEG SHMMNI /* max shared segs per process */
18
Olaf Hering4029a9172007-10-16 23:26:12 -070019#ifdef __KERNEL__
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <asm/shmparam.h>
Olaf Hering4029a9172007-10-16 23:26:12 -070021#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
23/* Obsolete, used only for backwards compatibility and libc5 compiles */
24struct shmid_ds {
25 struct ipc_perm shm_perm; /* operation perms */
26 int shm_segsz; /* size of segment (bytes) */
27 __kernel_time_t shm_atime; /* last attach time */
28 __kernel_time_t shm_dtime; /* last detach time */
29 __kernel_time_t shm_ctime; /* last change time */
30 __kernel_ipc_pid_t shm_cpid; /* pid of creator */
31 __kernel_ipc_pid_t shm_lpid; /* pid of last operator */
32 unsigned short shm_nattch; /* no. of current attaches */
33 unsigned short shm_unused; /* compatibility */
34 void *shm_unused2; /* ditto - used by DIPC */
35 void *shm_unused3; /* unused */
36};
37
38/* Include the definition of shmid64_ds and shminfo64 */
39#include <asm/shmbuf.h>
40
41/* permission flag for shmget */
42#define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */
43#define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */
44
45/* mode for attach */
46#define SHM_RDONLY 010000 /* read-only access */
47#define SHM_RND 020000 /* round attach address to SHMLBA boundary */
48#define SHM_REMAP 040000 /* take-over region on attach */
49#define SHM_EXEC 0100000 /* execution access */
50
51/* super user shmctl commands */
52#define SHM_LOCK 11
53#define SHM_UNLOCK 12
54
55/* ipcs ctl commands */
56#define SHM_STAT 13
57#define SHM_INFO 14
58
59/* Obsolete, used only for backwards compatibility */
60struct shminfo {
61 int shmmax;
62 int shmmin;
63 int shmmni;
64 int shmseg;
65 int shmall;
66};
67
68struct shm_info {
69 int used_ids;
70 unsigned long shm_tot; /* total allocated shm */
71 unsigned long shm_rss; /* total resident shm */
72 unsigned long shm_swp; /* total swapped shm */
73 unsigned long swap_attempts;
74 unsigned long swap_successes;
75};
76
77#ifdef __KERNEL__
78struct shmid_kernel /* private to the kernel */
79{
80 struct kern_ipc_perm shm_perm;
81 struct file * shm_file;
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 unsigned long shm_nattch;
83 unsigned long shm_segsz;
84 time_t shm_atim;
85 time_t shm_dtim;
86 time_t shm_ctim;
87 pid_t shm_cprid;
88 pid_t shm_lprid;
89 struct user_struct *mlock_user;
90};
91
92/* shm_mode upper byte flags */
93#define SHM_DEST 01000 /* segment will be destroyed on last detach */
94#define SHM_LOCKED 02000 /* segment will not be swapped */
95#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */
Badari Pulavartybf8f9722005-11-07 00:59:27 -080096#define SHM_NORESERVE 010000 /* don't check for reservations */
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
98#ifdef CONFIG_SYSVIPC
99long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr);
Adam Litke516dffd2007-03-01 15:46:08 -0800100extern int is_file_shm_hugepages(struct file *file);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101#else
102static inline long do_shmat(int shmid, char __user *shmaddr,
103 int shmflg, unsigned long *addr)
104{
105 return -ENOSYS;
106}
Adam Litke516dffd2007-03-01 15:46:08 -0800107static inline int is_file_shm_hugepages(struct file *file)
108{
109 return 0;
110}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111#endif
112
113#endif /* __KERNEL__ */
114
115#endif /* _LINUX_SHM_H_ */