#define _LINUX_MSG_H
#include <linux/ipc.h>
-#include <linux/list.h>
/* ipcs ctl commands */
#define MSG_STAT 11
unsigned short msgseg;
};
+/*
+ * Scaling factor to compute msgmni:
+ * the memory dedicated to msg queues (msgmni * msgmnb) should occupy
+ * at most 1/MSG_MEM_SCALE of the lowmem (see the formula in ipc/msg.c):
+ * up to 8MB : msgmni = 16 (MSGMNI)
+ * 4 GB : msgmni = 8K
+ * more than 16 GB : msgmni = 32K (IPCMNI)
+ */
+#define MSG_MEM_SCALE 32
+
#define MSGMNI 16 /* <= IPCMNI */ /* max # of msg queue identifiers */
#define MSGMAX 8192 /* <= INT_MAX */ /* max size of message (bytes) */
#define MSGMNB 16384 /* <= INT_MAX */ /* default max size of a message queue */
/* unused */
-#define MSGPOOL (MSGMNI*MSGMNB/1024) /* size in kilobytes of message pool */
+#define MSGPOOL (MSGMNI * MSGMNB) /* size in bytes of message pool */
#define MSGTQL MSGMNB /* number of system message headers */
#define MSGMAP MSGMNB /* number of entries in message map */
#define MSGSSZ 16 /* message segment size */
-#define __MSGSEG ((MSGPOOL*1024)/ MSGSSZ) /* max no. of segments */
+#define __MSGSEG (MSGPOOL / MSGSSZ) /* max no. of segments */
#define MSGSEG (__MSGSEG <= 0xffff ? __MSGSEG : 0xffff)
#ifdef __KERNEL__
+#include <linux/list.h>
/* one msg_msg structure for each message */
struct msg_msg {
/* one msq_queue structure for each present queue on the system */
struct msg_queue {
struct kern_ipc_perm q_perm;
- int q_id;
time_t q_stime; /* last msgsnd time */
time_t q_rtime; /* last msgrcv time */
time_t q_ctime; /* last change time */
struct list_head q_senders;
};
+/* Helper routines for sys_msgsnd and sys_msgrcv */
+extern long do_msgsnd(int msqid, long mtype, void __user *mtext,
+ size_t msgsz, int msgflg);
+extern long do_msgrcv(int msqid, long *pmtype, void __user *mtext,
+ size_t msgsz, long msgtyp, int msgflg);
+
#endif /* __KERNEL__ */
#endif /* _LINUX_MSG_H */