1 /* $FreeBSD: src/sys/kern/sysv_msg.c,v 1.23.2.5 2002/12/31 08:54:53 maxim Exp $ */
4 * Implementation of SVID messages
6 * Author: Daniel Boulet
8 * Copyright 1993 Daniel Boulet and RTMX Inc.
10 * This system call was implemented by Daniel Boulet under contract from RTMX.
12 * Redistribution and use in source forms, with and without modification,
13 * are permitted provided that this entire comment appears intact.
15 * Redistribution in binary form may occur without any restrictions.
16 * Obviously, it would be nice if you gave credit where credit is due
17 * but requiring it would be too onerous.
19 * This software is provided ``AS IS'' without any warranties of any kind.
22 #include "opt_sysvipc.h"
24 #include <sys/param.h>
25 #include <sys/systm.h>
26 #include <sys/sysproto.h>
27 #include <sys/kernel.h>
31 #include <sys/sysent.h>
32 #include <sys/sysctl.h>
33 #include <sys/malloc.h>
36 #include <sys/mplock2.h>
38 static MALLOC_DEFINE(M_MSG, "msg", "SVID compatible message queues");
40 static void msginit (void *);
45 static void msg_freehdr (struct msg *msghdr);
48 struct msg *msg_next; /* next msg in the chain */
49 long msg_type; /* type of this message */
50 /* >0 -> type of this message */
51 /* 0 -> free header */
52 u_short msg_ts; /* size of this message */
53 short msg_spot; /* location of start of msg in buffer */
58 #define MSGSSZ 8 /* Each segment must be 2^N long */
61 #define MSGSEG 2048 /* must be less than 32767 */
63 #define MSGMAX (MSGSSZ*MSGSEG)
65 #define MSGMNB 2048 /* max # of bytes in a queue */
75 * Based on the configuration parameters described in an SVR2 (yes, two)
76 * config(1m) man page.
78 * Each message is broken up and stored in segments that are msgssz bytes
79 * long. For efficiency reasons, this should be a power of two. Also,
80 * it doesn't make sense if it is less than 8 or greater than about 256.
81 * Consequently, msginit in kern/sysv_msg.c checks that msgssz is a power of
82 * two between 8 and 1024 inclusive (and panic's if it isn't).
84 struct msginfo msginfo = {
85 MSGMAX, /* max chars in a message */
86 MSGMNI, /* # of message queue identifiers */
87 MSGMNB, /* max chars in a queue */
88 MSGTQL, /* max messages in system */
89 MSGSSZ, /* size of a message segment */
90 /* (must be small power of 2 greater than 4) */
91 MSGSEG /* number of message segments */
95 * macros to convert between msqid_ds's and msqid's.
96 * (specific to this implementation)
98 #define MSQID(ix,ds) ((ix) & 0xffff | (((ds).msg_perm.seq << 16) & 0xffff0000))
99 #define MSQID_IX(id) ((id) & 0xffff)
100 #define MSQID_SEQ(id) (((id) >> 16) & 0xffff)
103 * The rest of this file is specific to this particular implementation.
107 short next; /* next segment in buffer */
108 /* -1 -> available */
109 /* 0..(MSGSEG-1) -> index of next segment */
112 #define MSG_LOCKED 01000 /* Is this msqid_ds locked? */
114 static int nfree_msgmaps; /* # of free map entries */
115 static short free_msgmaps; /* head of linked list of free map entries */
116 static struct msg *free_msghdrs;/* list of free msg headers */
117 static char *msgpool; /* MSGMAX byte long msg buffer pool */
118 static struct msgmap *msgmaps; /* MSGSEG msgmap structures */
119 static struct msg *msghdrs; /* MSGTQL msg headers */
120 static struct msqid_ds *msqids; /* MSGMNI msqid_ds struct's */
127 msginfo.msgmax = msginfo.msgseg * msginfo.msgssz;
128 msgpool = kmalloc(msginfo.msgmax, M_MSG, M_WAITOK);
129 msgmaps = kmalloc(sizeof(struct msgmap) * msginfo.msgseg, M_MSG, M_WAITOK);
130 msghdrs = kmalloc(sizeof(struct msg) * msginfo.msgtql, M_MSG, M_WAITOK);
131 msqids = kmalloc(sizeof(struct msqid_ds) * msginfo.msgmni, M_MSG, M_WAITOK);
134 * msginfo.msgssz should be a power of two for efficiency reasons.
135 * It is also pretty silly if msginfo.msgssz is less than 8
136 * or greater than about 256 so ...
140 while (i < 1024 && i != msginfo.msgssz)
142 if (i != msginfo.msgssz) {
143 kprintf("msginfo.msgssz=%d (0x%x)\n", msginfo.msgssz,
145 panic("msginfo.msgssz not a small power of 2");
148 if (msginfo.msgseg > 32767) {
149 kprintf("msginfo.msgseg=%d\n", msginfo.msgseg);
150 panic("msginfo.msgseg > 32767");
153 for (i = 0; i < msginfo.msgseg; i++) {
155 msgmaps[i-1].next = i;
156 msgmaps[i].next = -1; /* implies entry is available */
159 nfree_msgmaps = msginfo.msgseg;
161 for (i = 0; i < msginfo.msgtql; i++) {
162 msghdrs[i].msg_type = 0;
164 msghdrs[i-1].msg_next = &msghdrs[i];
165 msghdrs[i].msg_next = NULL;
167 free_msghdrs = &msghdrs[0];
169 for (i = 0; i < msginfo.msgmni; i++) {
170 msqids[i].msg_qbytes = 0; /* implies entry is available */
171 msqids[i].msg_perm.seq = 0; /* reset to a known value */
172 msqids[i].msg_perm.mode = 0;
175 SYSINIT(sysv_msg, SI_SUB_SYSV_MSG, SI_ORDER_FIRST, msginit, NULL);
178 msg_freehdr(struct msg *msghdr)
180 while (msghdr->msg_ts > 0) {
182 if (msghdr->msg_spot < 0 || msghdr->msg_spot >= msginfo.msgseg)
183 panic("msghdr->msg_spot out of range");
184 next = msgmaps[msghdr->msg_spot].next;
185 msgmaps[msghdr->msg_spot].next = free_msgmaps;
186 free_msgmaps = msghdr->msg_spot;
188 msghdr->msg_spot = next;
189 if (msghdr->msg_ts >= msginfo.msgssz)
190 msghdr->msg_ts -= msginfo.msgssz;
194 if (msghdr->msg_spot != -1)
195 panic("msghdr->msg_spot != -1");
196 msghdr->msg_next = free_msghdrs;
197 free_msghdrs = msghdr;
204 sys_msgctl(struct msgctl_args *uap)
206 struct thread *td = curthread;
207 struct proc *p = td->td_proc;
208 int msqid = uap->msqid;
210 struct msqid_ds *user_msqptr = uap->buf;
212 struct msqid_ds msqbuf;
213 struct msqid_ds *msqptr;
216 kprintf("call to msgctl(%d, %d, 0x%x)\n", msqid, cmd, user_msqptr);
219 if (!jail_sysvipc_allowed && td->td_ucred->cr_prison != NULL)
223 msqid = IPCID_TO_IX(msqid);
225 if (msqid < 0 || msqid >= msginfo.msgmni) {
227 kprintf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
234 msqptr = &msqids[msqid];
236 if (msqptr->msg_qbytes == 0) {
238 kprintf("no such msqid\n");
243 if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
245 kprintf("wrong sequence number\n");
257 if ((eval = ipcperm(p, &msqptr->msg_perm, IPC_M)) != 0)
259 /* Free the message headers */
260 msghdr = msqptr->msg_first;
261 while (msghdr != NULL) {
262 struct msg *msghdr_tmp;
264 /* Free the segments of each message */
265 msqptr->msg_cbytes -= msghdr->msg_ts;
268 msghdr = msghdr->msg_next;
269 msg_freehdr(msghdr_tmp);
272 if (msqptr->msg_cbytes != 0)
273 panic("msg_cbytes is screwed up");
274 if (msqptr->msg_qnum != 0)
275 panic("msg_qnum is screwed up");
277 msqptr->msg_qbytes = 0; /* Mark it as free */
279 wakeup((caddr_t)msqptr);
285 if ((eval = ipcperm(p, &msqptr->msg_perm, IPC_M)) != 0)
287 if ((eval = copyin(user_msqptr, &msqbuf, sizeof(msqbuf))) != 0)
289 if (msqbuf.msg_qbytes > msqptr->msg_qbytes) {
290 eval = priv_check(td, PRIV_ROOT);
294 if (msqbuf.msg_qbytes > msginfo.msgmnb) {
296 kprintf("can't increase msg_qbytes beyond %d (truncating)\n",
299 msqbuf.msg_qbytes = msginfo.msgmnb; /* silently restrict qbytes to system limit */
301 if (msqbuf.msg_qbytes == 0) {
303 kprintf("can't reduce msg_qbytes to 0\n");
305 eval = EINVAL; /* non-standard errno! */
308 msqptr->msg_perm.uid = msqbuf.msg_perm.uid; /* change the owner */
309 msqptr->msg_perm.gid = msqbuf.msg_perm.gid; /* change the owner */
310 msqptr->msg_perm.mode = (msqptr->msg_perm.mode & ~0777) |
311 (msqbuf.msg_perm.mode & 0777);
312 msqptr->msg_qbytes = msqbuf.msg_qbytes;
313 msqptr->msg_ctime = time_second;
317 if ((eval = ipcperm(p, &msqptr->msg_perm, IPC_R))) {
319 kprintf("requester doesn't have read access\n");
324 eval = copyout(msqptr, user_msqptr, sizeof(struct msqid_ds));
329 kprintf("invalid command %d\n", cmd);
337 uap->sysmsg_result = rval;
345 sys_msgget(struct msgget_args *uap)
347 struct thread *td = curthread;
350 int msgflg = uap->msgflg;
351 struct ucred *cred = td->td_ucred;
352 struct msqid_ds *msqptr = NULL;
355 kprintf("msgget(0x%x, 0%o)\n", key, msgflg);
357 if (!jail_sysvipc_allowed && cred->cr_prison != NULL)
363 if (key != IPC_PRIVATE) {
364 for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
365 msqptr = &msqids[msqid];
366 if (msqptr->msg_qbytes != 0 &&
367 msqptr->msg_perm.key == key)
370 if (msqid < msginfo.msgmni) {
372 kprintf("found public key\n");
374 if ((msgflg & IPC_CREAT) && (msgflg & IPC_EXCL)) {
376 kprintf("not exclusive\n");
381 if ((eval = ipcperm(td->td_proc, &msqptr->msg_perm, msgflg & 0700 ))) {
383 kprintf("requester doesn't have 0%o access\n",
393 kprintf("need to allocate the msqid_ds\n");
395 if (key == IPC_PRIVATE || (msgflg & IPC_CREAT)) {
396 for (msqid = 0; msqid < msginfo.msgmni; msqid++) {
398 * Look for an unallocated and unlocked msqid_ds.
399 * msqid_ds's can be locked by msgsnd or msgrcv while
400 * they are copying the message in/out. We can't
401 * re-use the entry until they release it.
403 msqptr = &msqids[msqid];
404 if (msqptr->msg_qbytes == 0 &&
405 (msqptr->msg_perm.mode & MSG_LOCKED) == 0)
408 if (msqid == msginfo.msgmni) {
410 kprintf("no more msqid_ds's available\n");
416 kprintf("msqid %d is available\n", msqid);
418 msqptr->msg_perm.key = key;
419 msqptr->msg_perm.cuid = cred->cr_uid;
420 msqptr->msg_perm.uid = cred->cr_uid;
421 msqptr->msg_perm.cgid = cred->cr_gid;
422 msqptr->msg_perm.gid = cred->cr_gid;
423 msqptr->msg_perm.mode = (msgflg & 0777);
424 /* Make sure that the returned msqid is unique */
425 msqptr->msg_perm.seq = (msqptr->msg_perm.seq + 1) & 0x7fff;
426 msqptr->msg_first = NULL;
427 msqptr->msg_last = NULL;
428 msqptr->msg_cbytes = 0;
429 msqptr->msg_qnum = 0;
430 msqptr->msg_qbytes = msginfo.msgmnb;
431 msqptr->msg_lspid = 0;
432 msqptr->msg_lrpid = 0;
433 msqptr->msg_stime = 0;
434 msqptr->msg_rtime = 0;
435 msqptr->msg_ctime = time_second;
438 kprintf("didn't find it and wasn't asked to create it\n");
445 /* Construct the unique msqid */
447 uap->sysmsg_result = IXSEQ_TO_IPCID(msqid, msqptr->msg_perm);
455 sys_msgsnd(struct msgsnd_args *uap)
457 struct thread *td = curthread;
458 int msqid = uap->msqid;
459 const void *user_msgp = uap->msgp;
460 size_t msgsz = uap->msgsz;
461 int msgflg = uap->msgflg;
462 int segs_needed, eval;
463 struct msqid_ds *msqptr;
468 kprintf("call to msgsnd(%d, 0x%x, %d, %d)\n", msqid, user_msgp, msgsz,
472 if (!jail_sysvipc_allowed && td->td_ucred->cr_prison != NULL)
476 msqid = IPCID_TO_IX(msqid);
478 if (msqid < 0 || msqid >= msginfo.msgmni) {
480 kprintf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
487 msqptr = &msqids[msqid];
488 if (msqptr->msg_qbytes == 0) {
490 kprintf("no such message queue id\n");
495 if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
497 kprintf("wrong sequence number\n");
503 if ((eval = ipcperm(td->td_proc, &msqptr->msg_perm, IPC_W))) {
505 kprintf("requester doesn't have write access\n");
511 segs_needed = (msgsz + msginfo.msgssz - 1) / msginfo.msgssz;
513 kprintf("msgsz=%d, msgssz=%d, segs_needed=%d\n", msgsz, msginfo.msgssz,
517 int need_more_resources = 0;
521 * (inside this loop in case msg_qbytes changes while we sleep)
524 if (msgsz > msqptr->msg_qbytes) {
526 kprintf("msgsz > msqptr->msg_qbytes\n");
532 if (msqptr->msg_perm.mode & MSG_LOCKED) {
534 kprintf("msqid is locked\n");
536 need_more_resources = 1;
538 if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes) {
540 kprintf("msgsz + msg_cbytes > msg_qbytes\n");
542 need_more_resources = 1;
544 if (segs_needed > nfree_msgmaps) {
546 kprintf("segs_needed > nfree_msgmaps\n");
548 need_more_resources = 1;
550 if (free_msghdrs == NULL) {
552 kprintf("no more msghdrs\n");
554 need_more_resources = 1;
557 if (need_more_resources) {
560 if ((msgflg & IPC_NOWAIT) != 0) {
562 kprintf("need more resources but caller doesn't want to wait\n");
568 if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0) {
570 kprintf("we don't own the msqid_ds\n");
574 /* Force later arrivals to wait for our
577 kprintf("we own the msqid_ds\n");
579 msqptr->msg_perm.mode |= MSG_LOCKED;
583 kprintf("goodnight\n");
585 eval = tsleep((caddr_t)msqptr, PCATCH, "msgwait", 0);
587 kprintf("good morning, eval=%d\n", eval);
590 msqptr->msg_perm.mode &= ~MSG_LOCKED;
593 kprintf("msgsnd: interrupted system call\n");
600 * Make sure that the msq queue still exists
603 if (msqptr->msg_qbytes == 0) {
605 kprintf("msqid deleted\n");
613 kprintf("got all the resources that we need\n");
620 * We have the resources that we need.
624 if (msqptr->msg_perm.mode & MSG_LOCKED)
625 panic("msg_perm.mode & MSG_LOCKED");
626 if (segs_needed > nfree_msgmaps)
627 panic("segs_needed > nfree_msgmaps");
628 if (msgsz + msqptr->msg_cbytes > msqptr->msg_qbytes)
629 panic("msgsz + msg_cbytes > msg_qbytes");
630 if (free_msghdrs == NULL)
631 panic("no more msghdrs");
634 * Re-lock the msqid_ds in case we page-fault when copying in the
638 if ((msqptr->msg_perm.mode & MSG_LOCKED) != 0)
639 panic("msqid_ds is already locked");
640 msqptr->msg_perm.mode |= MSG_LOCKED;
643 * Allocate a message header
646 msghdr = free_msghdrs;
647 free_msghdrs = msghdr->msg_next;
648 msghdr->msg_spot = -1;
649 msghdr->msg_ts = msgsz;
652 * Allocate space for the message
655 while (segs_needed > 0) {
656 if (nfree_msgmaps <= 0)
657 panic("not enough msgmaps");
658 if (free_msgmaps == -1)
659 panic("nil free_msgmaps");
662 panic("next too low #1");
663 if (next >= msginfo.msgseg)
664 panic("next out of range #1");
666 kprintf("allocating segment %d to message\n", next);
668 free_msgmaps = msgmaps[next].next;
670 msgmaps[next].next = msghdr->msg_spot;
671 msghdr->msg_spot = next;
676 * Copy in the message type
679 if ((eval = copyin(user_msgp, &msghdr->msg_type,
680 sizeof(msghdr->msg_type))) != 0) {
682 kprintf("error %d copying the message type\n", eval);
685 msqptr->msg_perm.mode &= ~MSG_LOCKED;
686 wakeup((caddr_t)msqptr);
689 user_msgp = (const char *)user_msgp + sizeof(msghdr->msg_type);
692 * Validate the message type
695 if (msghdr->msg_type < 1) {
697 msqptr->msg_perm.mode &= ~MSG_LOCKED;
698 wakeup((caddr_t)msqptr);
700 kprintf("mtype (%d) < 1\n", msghdr->msg_type);
707 * Copy in the message body
710 next = msghdr->msg_spot;
713 if (msgsz > msginfo.msgssz)
714 tlen = msginfo.msgssz;
718 panic("next too low #2");
719 if (next >= msginfo.msgseg)
720 panic("next out of range #2");
721 if ((eval = copyin(user_msgp, &msgpool[next * msginfo.msgssz],
724 kprintf("error %d copying in message segment\n", eval);
727 msqptr->msg_perm.mode &= ~MSG_LOCKED;
728 wakeup((caddr_t)msqptr);
732 user_msgp = (const char *)user_msgp + tlen;
733 next = msgmaps[next].next;
736 panic("didn't use all the msg segments");
739 * We've got the message. Unlock the msqid_ds.
742 msqptr->msg_perm.mode &= ~MSG_LOCKED;
745 * Make sure that the msqid_ds is still allocated.
748 if (msqptr->msg_qbytes == 0) {
750 wakeup((caddr_t)msqptr);
756 * Put the message into the queue
759 if (msqptr->msg_first == NULL) {
760 msqptr->msg_first = msghdr;
761 msqptr->msg_last = msghdr;
763 msqptr->msg_last->msg_next = msghdr;
764 msqptr->msg_last = msghdr;
766 msqptr->msg_last->msg_next = NULL;
768 msqptr->msg_cbytes += msghdr->msg_ts;
770 msqptr->msg_lspid = td->td_proc->p_pid;
771 msqptr->msg_stime = time_second;
773 wakeup((caddr_t)msqptr);
778 uap->sysmsg_result = 0;
786 sys_msgrcv(struct msgrcv_args *uap)
788 struct thread *td = curthread;
789 int msqid = uap->msqid;
790 void *user_msgp = uap->msgp;
791 size_t msgsz = uap->msgsz;
792 long msgtyp = uap->msgtyp;
793 int msgflg = uap->msgflg;
795 struct msqid_ds *msqptr;
801 kprintf("call to msgrcv(%d, 0x%x, %d, %ld, %d)\n", msqid, user_msgp,
802 msgsz, msgtyp, msgflg);
805 if (!jail_sysvipc_allowed && td->td_ucred->cr_prison != NULL)
809 msqid = IPCID_TO_IX(msqid);
811 if (msqid < 0 || msqid >= msginfo.msgmni) {
813 kprintf("msqid (%d) out of range (0<=msqid<%d)\n", msqid,
820 msqptr = &msqids[msqid];
821 if (msqptr->msg_qbytes == 0) {
823 kprintf("no such message queue id\n");
828 if (msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
830 kprintf("wrong sequence number\n");
836 if ((eval = ipcperm(td->td_proc, &msqptr->msg_perm, IPC_R))) {
838 kprintf("requester doesn't have read access\n");
844 while (msghdr == NULL) {
846 msghdr = msqptr->msg_first;
847 if (msghdr != NULL) {
848 if (msgsz < msghdr->msg_ts &&
849 (msgflg & MSG_NOERROR) == 0) {
851 kprintf("first message on the queue is too big (want %d, got %d)\n",
852 msgsz, msghdr->msg_ts);
857 if (msqptr->msg_first == msqptr->msg_last) {
858 msqptr->msg_first = NULL;
859 msqptr->msg_last = NULL;
861 msqptr->msg_first = msghdr->msg_next;
862 if (msqptr->msg_first == NULL)
863 panic("msg_first/last screwed up #1");
867 struct msg *previous;
871 prev = &(msqptr->msg_first);
872 while ((msghdr = *prev) != NULL) {
874 * Is this message's type an exact match or is
875 * this message's type less than or equal to
876 * the absolute value of a negative msgtyp?
877 * Note that the second half of this test can
878 * NEVER be true if msgtyp is positive since
879 * msg_type is always positive!
882 if (msgtyp == msghdr->msg_type ||
883 msghdr->msg_type <= -msgtyp) {
885 kprintf("found message type %d, requested %d\n",
886 msghdr->msg_type, msgtyp);
888 if (msgsz < msghdr->msg_ts &&
889 (msgflg & MSG_NOERROR) == 0) {
891 kprintf("requested message on the queue is too big (want %d, got %d)\n",
892 msgsz, msghdr->msg_ts);
897 *prev = msghdr->msg_next;
898 if (msghdr == msqptr->msg_last) {
899 if (previous == NULL) {
902 panic("msg_first/last screwed up #2");
910 panic("msg_first/last screwed up #3");
918 prev = &(msghdr->msg_next);
923 * We've either extracted the msghdr for the appropriate
924 * message or there isn't one.
925 * If there is one then bail out of this loop.
932 * Hmph! No message found. Does the user want to wait?
935 if ((msgflg & IPC_NOWAIT) != 0) {
937 kprintf("no appropriate message found (msgtyp=%d)\n",
940 /* The SVID says to return ENOMSG. */
944 /* Unfortunately, BSD doesn't define that code yet! */
951 * Wait for something to happen
955 kprintf("msgrcv: goodnight\n");
957 eval = tsleep((caddr_t)msqptr, PCATCH, "msgwait", 0);
959 kprintf("msgrcv: good morning (eval=%d)\n", eval);
964 kprintf("msgsnd: interrupted system call\n");
971 * Make sure that the msq queue still exists
974 if (msqptr->msg_qbytes == 0 ||
975 msqptr->msg_perm.seq != IPCID_TO_SEQ(uap->msqid)) {
977 kprintf("msqid deleted\n");
985 * Return the message to the user.
987 * First, do the bookkeeping (before we risk being interrupted).
990 msqptr->msg_cbytes -= msghdr->msg_ts;
992 msqptr->msg_lrpid = td->td_proc->p_pid;
993 msqptr->msg_rtime = time_second;
996 * Make msgsz the actual amount that we'll be returning.
997 * Note that this effectively truncates the message if it is too long
998 * (since msgsz is never increased).
1002 kprintf("found a message, msgsz=%d, msg_ts=%d\n", msgsz,
1005 if (msgsz > msghdr->msg_ts)
1006 msgsz = msghdr->msg_ts;
1009 * Return the type to the user.
1012 eval = copyout((caddr_t)&(msghdr->msg_type), user_msgp,
1013 sizeof(msghdr->msg_type));
1016 kprintf("error (%d) copying out message type\n", eval);
1018 msg_freehdr(msghdr);
1019 wakeup((caddr_t)msqptr);
1022 user_msgp = (char *)user_msgp + sizeof(msghdr->msg_type);
1025 * Return the segments to the user
1028 next = msghdr->msg_spot;
1029 for (len = 0; len < msgsz; len += msginfo.msgssz) {
1032 if (msgsz - len > msginfo.msgssz)
1033 tlen = msginfo.msgssz;
1037 panic("next too low #3");
1038 if (next >= msginfo.msgseg)
1039 panic("next out of range #3");
1040 eval = copyout((caddr_t)&msgpool[next * msginfo.msgssz],
1044 kprintf("error (%d) copying out message segment\n",
1047 msg_freehdr(msghdr);
1048 wakeup((caddr_t)msqptr);
1051 user_msgp = (char *)user_msgp + tlen;
1052 next = msgmaps[next].next;
1056 * Done, return the actual number of bytes copied out.
1059 msg_freehdr(msghdr);
1060 wakeup((caddr_t)msqptr);
1065 uap->sysmsg_result = msgsz;
1070 sysctl_msqids(SYSCTL_HANDLER_ARGS)
1073 return (SYSCTL_OUT(req, msqids,
1074 sizeof(struct msqid_ds) * msginfo.msgmni));
1077 TUNABLE_INT("kern.ipc.msgseg", &msginfo.msgseg);
1078 TUNABLE_INT("kern.ipc.msgssz", &msginfo.msgssz);
1079 TUNABLE_INT("kern.ipc.msgmni", &msginfo.msgmni);
1081 SYSCTL_INT(_kern_ipc, OID_AUTO, msgmax, CTLFLAG_RD, &msginfo.msgmax, 0,
1082 "Max characters in message");
1083 SYSCTL_INT(_kern_ipc, OID_AUTO, msgmni, CTLFLAG_RD, &msginfo.msgmni, 0,
1084 "Max message queue identifiers");
1085 SYSCTL_INT(_kern_ipc, OID_AUTO, msgmnb, CTLFLAG_RD, &msginfo.msgmnb, 0,
1086 "Max characters in message queue");
1087 SYSCTL_INT(_kern_ipc, OID_AUTO, msgtql, CTLFLAG_RD, &msginfo.msgtql, 0,
1088 "Max SVID messages in system");
1089 SYSCTL_INT(_kern_ipc, OID_AUTO, msgssz, CTLFLAG_RD, &msginfo.msgssz, 0,
1090 "Power-of-two size of a message segment");
1091 SYSCTL_INT(_kern_ipc, OID_AUTO, msgseg, CTLFLAG_RD, &msginfo.msgseg, 0,
1092 "Number of message segments");
1093 SYSCTL_PROC(_kern_ipc, OID_AUTO, msqids, CTLFLAG_RD,
1094 NULL, 0, sysctl_msqids, "", "Message queue IDs");