include/sys/msg_impl.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #ifndef _SYS_MSG_IMPL_H
  27 #define _SYS_MSG_IMPL_H
  28
  29 #include <sys/ipc_impl.h>
  30 #if defined(_KERNEL) || defined(_KMEMUSER)
  31 #include <sys/msg.h>
  32 #include <sys/t_lock.h>
  33 #include <sys/list.h>
  34 #endif
  35
  36 #ifdef  __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 /*
  41  * Argument vectors for the various flavors of msgsys().
  42  */
  43
  44 #define MSGGET  0
  45 #define MSGCTL  1
  46 #define MSGRCV  2
  47 #define MSGSND  3
  48 #define MSGIDS  4
  49 #define MSGSNAP 5
  50
  51 #if defined(_KERNEL) || defined(_KMEMUSER)
  52
  53 typedef struct  msgq_wakeup {
  54         list_node_t     msgw_list;
  55         long            msgw_type;      /* Message type request. */
  56         long            msgw_snd_wake;  /* Type of msg from msgsnd */
  57         size_t          msgw_snd_size;  /* Designates size of the msg sending */
  58         kthread_t       *msgw_thrd;     /* Thread waiting */
  59         kcondvar_t      msgw_wake_cv;   /* waiting on this */
  60 } msgq_wakeup_t;
  61
  62
  63 typedef struct msg_select {
  64         msgq_wakeup_t *(*selection)();
  65         struct msg_select *next_selection;
  66 } msg_select_t;
  67
  68 /*
  69  * There is one msg structure for each message in the system.
  70  */
  71 struct msg {
  72         list_node_t     msg_node;       /* message list node */
  73         long            msg_type;       /* message type */
  74         size_t          msg_size;       /* message text size */
  75         void            *msg_addr;      /* message text address */
  76         long            msg_flags;      /* message flags */
  77         long            msg_copycnt;    /* current # of copyouts on message */
  78 };
  79
  80 /*
  81  * Per message flags
  82  */
  83 #define MSG_RCVCOPY     00001   /* msgrcv is copying out this message */
  84 #define MSG_UNLINKED    00002   /* msg has been unlinked from queue */
  85
  86 /*
  87  * msg_rcv_cv is now an array of kcondvar_t for performance reason.
  88  * We use multiple condition variables (kcondvar_t) to avoid needing
  89  * to wake all readers when sending a single message.
  90  */
  91
  92 #define MSG_NEG_INTERVAL 8
  93 #define MSG_MAX_QNUM    64
  94 #define MSG_MAX_QNUM_CV 65
  95
  96 typedef struct kmsqid {
  97         kipc_perm_t     msg_perm;       /* operation permission struct */
  98         list_t          msg_list;       /* list of messages on q */
  99         msglen_t        msg_cbytes;     /* current # bytes on q */
 100         msgqnum_t       msg_qnum;       /* # of messages on q */
 101         msgqnum_t       msg_qmax;       /* max # of messages on q */
 102         msglen_t        msg_qbytes;     /* max # of bytes on q */
 103         pid_t           msg_lspid;      /* pid of last msgsnd */
 104         pid_t           msg_lrpid;      /* pid of last msgrcv */
 105         time_t          msg_stime;      /* last msgsnd time */
 106         time_t          msg_rtime;      /* last msgrcv time */
 107         time_t          msg_ctime;      /* last change time */
 108         uint_t          msg_snd_cnt;    /* # of waiting senders */
 109         uint_t          msg_rcv_cnt;    /* # of waiting receivers */
 110         uint64_t        msg_lowest_type; /* Smallest type on queue */
 111         /*
 112          * linked list of routines used to determine what to wake up next.
 113          *      msg_fnd_sndr:   Routines for waking up readers waiting
 114          *                      for a message from the sender.
 115          *      msg_fnd_rdr:    Routines for waking up readers waiting
 116          *                      for a copyout to finish.
 117          */
 118         msg_select_t    *msg_fnd_sndr;
 119         msg_select_t    *msg_fnd_rdr;
 120         /*
 121          * Various counts and queues for controlling the sleeping
 122          * and waking up of processes that are waiting for various
 123          * message queue events.
 124          *
 125          * msg_cpy_block:   List of receiving threads that are blocked because
 126          *                  the message of choice is being copied out.
 127          * msg_wait_snd:    List of receiving threads whose type specifier
 128          *                  is positive or 0 but are blocked because there
 129          *                  are no matches.
 130          * msg_wait_snd_ngt:
 131          *                  List of receiving threads whose type specifier is
 132          *                  negative message type but are blocked because
 133          *                  there are no types that qualify.
 134          * msg_wait_rcv:    List of sending threads that are blocked because
 135          *                  there is no room left on the message queue.
 136          */
 137         kcondvar_t      msg_snd_cv;
 138         list_t          msg_cpy_block;
 139         list_t          msg_wait_snd[MSG_MAX_QNUM_CV];
 140         list_t          msg_wait_snd_ngt[MSG_MAX_QNUM_CV];
 141         list_t          msg_wait_rcv;
 142         size_t          msg_snd_smallest; /* Smallest msg on send wait list */
 143         int             msg_ngt_cnt;    /* # of negative receivers blocked */
 144         char            msg_neg_copy;   /* Neg type copy underway */
 145 } kmsqid_t;
 146
 147 #endif  /* _KERNEL */
 148
 149 #if defined(_SYSCALL32)
 150 /*
 151  * LP64 view of the ILP32 msgbuf structure
 152  */
 153 struct ipcmsgbuf32 {
 154         int32_t mtype;          /* message type */
 155         char    mtext[1];       /* message text */
 156 };
 157
 158 /*
 159  * LP64 view of the ILP32 msgsnap_head and msgsnap_mhead structures
 160  */
 161 struct msgsnap_head32 {
 162         size32_t msgsnap_size;  /* bytes consumed/required in the buffer */
 163         size32_t msgsnap_nmsg;  /* number of messages in the buffer */
 164 };
 165
 166 struct msgsnap_mhead32 {
 167         size32_t msgsnap_mlen;  /* number of bytes in message that follows */
 168         int32_t msgsnap_mtype;  /* message type */
 169 };
 170
 171 /*
 172  * LP64 view of the ILP32 msqid_ds structure
 173  */
 174 struct msqid_ds32 {
 175         struct ipc_perm32 msg_perm;     /* operation permission struct */
 176         caddr32_t       msg_first;      /* ptr to first message on q */
 177         caddr32_t       msg_last;       /* ptr to last message on q */
 178         uint32_t        msg_cbytes;     /* current # bytes on q */
 179         uint32_t        msg_qnum;       /* # of messages on q */
 180         uint32_t        msg_qbytes;     /* max # of bytes on q */
 181         pid32_t         msg_lspid;      /* pid of last msgsnd */
 182         pid32_t         msg_lrpid;      /* pid of last msgrcv */
 183         time32_t        msg_stime;      /* last msgsnd time */
 184         int32_t         msg_pad1;       /* reserved for time_t expansion */
 185         time32_t        msg_rtime;      /* last msgrcv time */
 186         int32_t         msg_pad2;       /* time_t expansion */
 187         time32_t        msg_ctime;      /* last change time */
 188         int32_t         msg_pad3;       /* time expansion */
 189         int16_t         msg_cv;
 190         int16_t         msg_qnum_cv;
 191         int32_t         msg_pad4[3];    /* reserve area */
 192 };
 193 #endif  /* _SYSCALL32 */
 194
 195 #ifdef  __cplusplus
 196 }
 197 #endif
 198
 199 #endif  /* _SYS_MSG_IMPL_H */