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#ifndef _LINUX_SHM_H_
#define _LINUX_SHM_H_
#include <linux/ipc.h>
#include <asm/page.h>
/*
* SHMMAX, SHMMNI and SHMALL are upper limits are defaults which can
* be increased by sysctl
*/
#define SHMMAX 0x2000000 /* max shared seg size (bytes) */
#define SHMMIN 1 /* min shared seg size (bytes) */
#define SHMMNI 4096 /* max num of segs system wide */
#define SHMALL (SHMMAX/PAGE_SIZE*(SHMMNI/16)) /* max shm system wide (pages) */
#define SHMSEG SHMMNI /* max shared segs per process */
#include <asm/shmparam.h>
/* Obsolete, used only for backwards compatibility and libc5 compiles */
struct shmid_ds {
struct ipc_perm shm_perm; /* operation perms */
int shm_segsz; /* size of segment (bytes) */
__kernel_time_t shm_atime; /* last attach time */
__kernel_time_t shm_dtime; /* last detach time */
__kernel_time_t shm_ctime; /* last change time */
__kernel_ipc_pid_t shm_cpid; /* pid of creator */
__kernel_ipc_pid_t shm_lpid; /* pid of last operator */
unsigned short shm_nattch; /* no. of current attaches */
unsigned short shm_unused; /* compatibility */
void *shm_unused2; /* ditto - used by DIPC */
void *shm_unused3; /* unused */
};
/* Include the definition of shmid64_ds and shminfo64 */
#include <asm/shmbuf.h>
/* permission flag for shmget */
#define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */
#define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */
/* mode for attach */
#define SHM_RDONLY 010000 /* read-only access */
#define SHM_RND 020000 /* round attach address to SHMLBA boundary */
#define SHM_REMAP 040000 /* take-over region on attach */
/* super user shmctl commands */
#define SHM_LOCK 11
#define SHM_UNLOCK 12
/* ipcs ctl commands */
#define SHM_STAT 13
#define SHM_INFO 14
/* Obsolete, used only for backwards compatibility */
struct shminfo {
int shmmax;
int shmmin;
int shmmni;
int shmseg;
int shmall;
};
struct shm_info {
int used_ids;
unsigned long shm_tot; /* total allocated shm */
unsigned long shm_rss; /* total resident shm */
unsigned long shm_swp; /* total swapped shm */
unsigned long swap_attempts;
unsigned long swap_successes;
};
#ifdef __KERNEL__
/* shm_mode upper byte flags */
#define SHM_DEST 01000 /* segment will be destroyed on last detach */
#define SHM_LOCKED 02000 /* segment will not be swapped */
asmlinkage long sys_shmget (key_t key, size_t size, int flag);
asmlinkage long sys_shmat (int shmid, char *shmaddr, int shmflg, unsigned long *addr);
asmlinkage long sys_shmdt (char *shmaddr);
asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds *buf);
extern void shm_unuse(swp_entry_t entry, struct page *page);
#endif /* __KERNEL__ */
#endif /* _LINUX_SHM_H_ */
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