1 #ifndef _LINUX_SHM_H_ 2 #define _LINUX_SHM_H_ 3 4 #include <linux/ipc.h> 5 #include <linux/errno.h> 6 #include <unistd.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/getpagesize()*(SHMMNI/16)) 17 #define SHMSEG SHMMNI /* max shared segs per process */ 18 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 #define SHM_EXEC 0100000 /* execution access */ 47 48 /* super user shmctl commands */ 49 #define SHM_LOCK 11 50 #define SHM_UNLOCK 12 51 52 /* ipcs ctl commands */ 53 #define SHM_STAT 13 54 #define SHM_INFO 14 55 56 /* Obsolete, used only for backwards compatibility */ 57 struct shminfo { 58 int shmmax; 59 int shmmin; 60 int shmmni; 61 int shmseg; 62 int shmall; 63 }; 64 65 struct shm_info { 66 int used_ids; 67 unsigned long shm_tot; /* total allocated shm */ 68 unsigned long shm_rss; /* total resident shm */ 69 unsigned long shm_swp; /* total swapped shm */ 70 unsigned long swap_attempts; 71 unsigned long swap_successes; 72 }; 73 74 75 #endif /* _LINUX_SHM_H_ */ 76