1 #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 19 #ifdef __KERNEL__ 20 #include <asm/shmparam.h> 21 #endif 22 23 /* Obsolete, used only for backwards compatibility and libc5 compiles */ 24 struct 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 */ 60 struct shminfo { 61 int shmmax; 62 int shmmin; 63 int shmmni; 64 int shmseg; 65 int shmall; 66 }; 67 68 struct 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__ 78 struct shmid_kernel /* private to the kernel */ 79 { 80 struct kern_ipc_perm shm_perm; 81 struct file * shm_file; 82 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 */ 96 #define SHM_NORESERVE 010000 /* don't check for reservations */ 97 98 #ifdef CONFIG_SYSVIPC 99 long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr); 100 extern int is_file_shm_hugepages(struct file *file); 101 #else 102 static inline long do_shmat(int shmid, char __user *shmaddr, 103 int shmflg, unsigned long *addr) 104 { 105 return -ENOSYS; 106 } 107 static inline int is_file_shm_hugepages(struct file *file) 108 { 109 return 0; 110 } 111 #endif 112 113 #endif /* __KERNEL__ */ 114 115 #endif /* _LINUX_SHM_H_ */ 116