1 #ifndef _LINUX_SHM_H_ 2 #define _LINUX_SHM_H_ 3 4 #include <linux/ipc.h> 5 #include <asm/page.h> 6 7 /* 8 * SHMMAX, SHMMNI and SHMALL are upper limits are defaults which can 9 * be increased by sysctl 10 */ 11 12 #define SHMMAX 0x2000000 /* max shared seg size (bytes) */ 13 #define SHMMIN 1 /* min shared seg size (bytes) */ 14 #define SHMMNI 4096 /* max num of segs system wide */ 15 #define SHMALL (SHMMAX/PAGE_SIZE*(SHMMNI/16)) /* max shm system wide (pages) */ 16 #define SHMSEG SHMMNI /* max shared segs per process */ 17 18 #include <asm/shmparam.h> 19 20 /* Obsolete, used only for backwards compatibility and libc5 compiles */ 21 struct shmid_ds { 22 struct ipc_perm shm_perm; /* operation perms */ 23 int shm_segsz; /* size of segment (bytes) */ 24 __kernel_time_t shm_atime; /* last attach time */ 25 __kernel_time_t shm_dtime; /* last detach time */ 26 __kernel_time_t shm_ctime; /* last change time */ 27 __kernel_ipc_pid_t shm_cpid; /* pid of creator */ 28 __kernel_ipc_pid_t shm_lpid; /* pid of last operator */ 29 unsigned short shm_nattch; /* no. of current attaches */ 30 unsigned short shm_unused; /* compatibility */ 31 void *shm_unused2; /* ditto - used by DIPC */ 32 void *shm_unused3; /* unused */ 33 }; 34 35 /* Include the definition of shmid64_ds and shminfo64 */ 36 #include <asm/shmbuf.h> 37 38 /* permission flag for shmget */ 39 #define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */ 40 #define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */ 41 42 /* mode for attach */ 43 #define SHM_RDONLY 010000 /* read-only access */ 44 #define SHM_RND 020000 /* round attach address to SHMLBA boundary */ 45 #define SHM_REMAP 040000 /* take-over region on attach */ 46 47 /* super user shmctl commands */ 48 #define SHM_LOCK 11 49 #define SHM_UNLOCK 12 50 51 /* ipcs ctl commands */ 52 #define SHM_STAT 13 53 #define SHM_INFO 14 54 55 /* Obsolete, used only for backwards compatibility */ 56 struct shminfo { 57 int shmmax; 58 int shmmin; 59 int shmmni; 60 int shmseg; 61 int shmall; 62 }; 63 64 struct shm_info { 65 int used_ids; 66 unsigned long shm_tot; /* total allocated shm */ 67 unsigned long shm_rss; /* total resident shm */ 68 unsigned long shm_swp; /* total swapped shm */ 69 unsigned long swap_attempts; 70 unsigned long swap_successes; 71 }; 72 73 #ifdef __KERNEL__ 74 75 /* shm_mode upper byte flags */ 76 #define SHM_DEST 01000 /* segment will be destroyed on last detach */ 77 #define SHM_LOCKED 02000 /* segment will not be swapped */ 78 79 asmlinkage long sys_shmget (key_t key, size_t size, int flag); 80 asmlinkage long sys_shmat (int shmid, char *shmaddr, int shmflg, unsigned long *addr); 81 asmlinkage long sys_shmdt (char *shmaddr); 82 asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds *buf); 83 extern void shm_unuse(swp_entry_t entry, struct page *page); 84 85 #endif /* __KERNEL__ */ 86 87 #endif /* _LINUX_SHM_H_ */ 88