1 #ifndef _LINUX_MSG_H 2 #define _LINUX_MSG_H 3 4 #include <linux/ipc.h> 5 6 /* ipcs ctl commands */ 7 #define MSG_STAT 11 8 #define MSG_INFO 12 9 10 /* msgrcv options */ 11 #define MSG_NOERROR 010000 /* no error if message is too big */ 12 #define MSG_EXCEPT 020000 /* recv any msg except of specified type.*/ 13 14 /* Obsolete, used only for backwards compatibility and libc5 compiles */ 15 struct msqid_ds { 16 struct ipc_perm msg_perm; 17 struct msg *msg_first; /* first message on queue,unused */ 18 struct msg *msg_last; /* last message in queue,unused */ 19 __kernel_time_t msg_stime; /* last msgsnd time */ 20 __kernel_time_t msg_rtime; /* last msgrcv time */ 21 __kernel_time_t msg_ctime; /* last change time */ 22 unsigned long msg_lcbytes; /* Reuse junk fields for 32 bit */ 23 unsigned long msg_lqbytes; /* ditto */ 24 unsigned short msg_cbytes; /* current number of bytes on queue */ 25 unsigned short msg_qnum; /* number of messages in queue */ 26 unsigned short msg_qbytes; /* max number of bytes on queue */ 27 __kernel_ipc_pid_t msg_lspid; /* pid of last msgsnd */ 28 __kernel_ipc_pid_t msg_lrpid; /* last receive pid */ 29 }; 30 31 /* Include the definition of msqid64_ds */ 32 #include <asm/msgbuf.h> 33 34 /* message buffer for msgsnd and msgrcv calls */ 35 struct msgbuf { 36 long mtype; /* type of message */ 37 char mtext[1]; /* message text */ 38 }; 39 40 /* buffer for msgctl calls IPC_INFO, MSG_INFO */ 41 struct msginfo { 42 int msgpool; 43 int msgmap; 44 int msgmax; 45 int msgmnb; 46 int msgmni; 47 int msgssz; 48 int msgtql; 49 unsigned short msgseg; 50 }; 51 52 /* 53 * Scaling factor to compute msgmni: 54 * the memory dedicated to msg queues (msgmni * msgmnb) should occupy 55 * at most 1/MSG_MEM_SCALE of the lowmem (see the formula in ipc/msg.c): 56 * up to 8MB : msgmni = 16 (MSGMNI) 57 * 4 GB : msgmni = 8K 58 * more than 16 GB : msgmni = 32K (IPCMNI) 59 */ 60 #define MSG_MEM_SCALE 32 61 62 #define MSGMNI 16 /* <= IPCMNI */ /* max # of msg queue identifiers */ 63 #define MSGMAX 8192 /* <= INT_MAX */ /* max size of message (bytes) */ 64 #define MSGMNB 16384 /* <= INT_MAX */ /* default max size of a message queue */ 65 66 /* unused */ 67 #define MSGPOOL (MSGMNI * MSGMNB / 1024) /* size in kbytes of message pool */ 68 #define MSGTQL MSGMNB /* number of system message headers */ 69 #define MSGMAP MSGMNB /* number of entries in message map */ 70 #define MSGSSZ 16 /* message segment size */ 71 #define __MSGSEG ((MSGPOOL * 1024) / MSGSSZ) /* max no. of segments */ 72 #define MSGSEG (__MSGSEG <= 0xffff ? __MSGSEG : 0xffff) 73 74 75 #endif /* _LINUX_MSG_H */ 76