shm.h

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#ifndef _LINUX_SHM_H_
#define _LINUX_SHM_H_

#include <asm/page.h>
#include <uapi/linux/shm.h>

#define SHMALL (SHMMAX/PAGE_SIZE*(SHMMNI/16)) /* max shm system wide (pages) */
#include <asm/shmparam.h>
struct shmid_kernel /* private to the kernel */
{   
    struct kern_ipc_perm    shm_perm;
    struct file *       shm_file;
    unsigned long       shm_nattch;
    unsigned long       shm_segsz;
    time_t          shm_atim;
    time_t          shm_dtim;
    time_t          shm_ctim;
    pid_t           shm_cprid;
    pid_t           shm_lprid;
    struct user_struct  *mlock_user;

    /* The task created the shm object.  NULL if the task is dead. */
    struct task_struct  *shm_creator;
};

/* 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 */
#define SHM_HUGETLB     04000   /* segment will use huge TLB pages */
#define SHM_NORESERVE   010000  /* don't check for reservations */

#ifdef CONFIG_SYSVIPC
long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
          unsigned long shmlba);
extern int is_file_shm_hugepages(struct file *file);
extern void exit_shm(struct task_struct *task);
#else
static inline long do_shmat(int shmid, char __user *shmaddr,
                int shmflg, unsigned long *addr,
                unsigned long shmlba)
{
    return -ENOSYS;
}
static inline int is_file_shm_hugepages(struct file *file)
{
    return 0;
}
static inline void exit_shm(struct task_struct *task)
{
}
#endif

#endif /* _LINUX_SHM_H_ */