include/linux/shm.h

   1 #ifndef _LINUX_SHM_H_
   2 #define _LINUX_SHM_H_
   3
   4 #include <asm/page.h>
   5 #include <uapi/linux/shm.h>
   6
   7 #define SHMALL (SHMMAX/PAGE_SIZE*(SHMMNI/16)) /* max shm system wide (pages) */
   8 #include <asm/shmparam.h>
   9 struct shmid_kernel /* private to the kernel */
  10 {
  11         struct kern_ipc_perm    shm_perm;
  12         struct file *           shm_file;
  13         unsigned long           shm_nattch;
  14         unsigned long           shm_segsz;
  15         time_t                  shm_atim;
  16         time_t                  shm_dtim;
  17         time_t                  shm_ctim;
  18         pid_t                   shm_cprid;
  19         pid_t                   shm_lprid;
  20         struct user_struct      *mlock_user;
  21
  22         /* The task created the shm object.  NULL if the task is dead. */
  23         struct task_struct      *shm_creator;
  24 };
  25
  26 /* shm_mode upper byte flags */
  27 #define SHM_DEST        01000   /* segment will be destroyed on last detach */
  28 #define SHM_LOCKED      02000   /* segment will not be swapped */
  29 #define SHM_HUGETLB     04000   /* segment will use huge TLB pages */
  30 #define SHM_NORESERVE   010000  /* don't check for reservations */
  31
  32 #ifdef CONFIG_SYSVIPC
  33 long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
  34               unsigned long shmlba);
  35 extern int is_file_shm_hugepages(struct file *file);
  36 extern void exit_shm(struct task_struct *task);
  37 #else
  38 static inline long do_shmat(int shmid, char __user *shmaddr,
  39                             int shmflg, unsigned long *addr,
  40                             unsigned long shmlba)
  41 {
  42         return -ENOSYS;
  43 }
  44 static inline int is_file_shm_hugepages(struct file *file)
  45 {
  46         return 0;
  47 }
  48 static inline void exit_shm(struct task_struct *task)
  49 {
  50 }
  51 #endif
  52
  53 #endif /* _LINUX_SHM_H_ */