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> 9struct 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/* Bits [26:31] are reserved */ 33 34/* 35 * When SHM_HUGETLB is set bits [26:31] encode the log2 of the huge page size. 36 * This gives us 6 bits, which is enough until someone invents 128 bit address 37 * spaces. 38 * 39 * Assume these are all power of twos. 40 * When 0 use the default page size. 41 */ 42#define SHM_HUGE_SHIFT 26 43#define SHM_HUGE_MASK 0x3f 44#define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT) 45#define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT) 46 47#ifdef CONFIG_SYSVIPC 48long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr, 49 unsigned long shmlba); 50extern int is_file_shm_hugepages(struct file *file); 51extern void exit_shm(struct task_struct *task); 52#else 53static inline long do_shmat(int shmid, char __user *shmaddr, 54 int shmflg, unsigned long *addr, 55 unsigned long shmlba) 56{ 57 return -ENOSYS; 58} 59static inline int is_file_shm_hugepages(struct file *file) 60{ 61 return 0; 62} 63static inline void exit_shm(struct task_struct *task) 64{ 65} 66#endif 67 68#endif /* _LINUX_SHM_H_ */ 69