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1 /*      $NetBSD: sysv_shm.c,v 1.23 1994/07/04 23:25:12 glass Exp $      */
2 /*-
3  * Copyright (c) 1994 Adam Glass and Charles Hannum.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *      This product includes software developed by Adam Glass and Charles
16  *      Hannum.
17  * 4. The names of the authors may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*-
32  * Copyright (c) 2003-2005 McAfee, Inc.
33  * All rights reserved.
34  *
35  * This software was developed for the FreeBSD Project in part by McAfee
36  * Research, the Security Research Division of McAfee, Inc under DARPA/SPAWAR
37  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS research
38  * program.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  */
61
62 #include <sys/cdefs.h>
63 __FBSDID("$FreeBSD$");
64
65 #include "opt_compat.h"
66 #include "opt_sysvipc.h"
67
68 #include <sys/param.h>
69 #include <sys/systm.h>
70 #include <sys/kernel.h>
71 #include <sys/limits.h>
72 #include <sys/lock.h>
73 #include <sys/sysctl.h>
74 #include <sys/shm.h>
75 #include <sys/proc.h>
76 #include <sys/malloc.h>
77 #include <sys/mman.h>
78 #include <sys/module.h>
79 #include <sys/mutex.h>
80 #include <sys/racct.h>
81 #include <sys/resourcevar.h>
82 #include <sys/rwlock.h>
83 #include <sys/stat.h>
84 #include <sys/syscall.h>
85 #include <sys/syscallsubr.h>
86 #include <sys/sysent.h>
87 #include <sys/sysproto.h>
88 #include <sys/jail.h>
89
90 #include <security/mac/mac_framework.h>
91
92 #include <vm/vm.h>
93 #include <vm/vm_param.h>
94 #include <vm/pmap.h>
95 #include <vm/vm_object.h>
96 #include <vm/vm_map.h>
97 #include <vm/vm_page.h>
98 #include <vm/vm_pager.h>
99
100 FEATURE(sysv_shm, "System V shared memory segments support");
101
102 static MALLOC_DEFINE(M_SHM, "shm", "SVID compatible shared memory segments");
103
104 static int shmget_allocate_segment(struct thread *td,
105     struct shmget_args *uap, int mode);
106 static int shmget_existing(struct thread *td, struct shmget_args *uap,
107     int mode, int segnum);
108
109 #define SHMSEG_FREE             0x0200
110 #define SHMSEG_REMOVED          0x0400
111 #define SHMSEG_ALLOCATED        0x0800
112 #define SHMSEG_WANTED           0x1000
113
114 static int shm_last_free, shm_nused, shmalloced;
115 vm_size_t shm_committed;
116 static struct shmid_kernel      *shmsegs;
117
118 struct shmmap_state {
119         vm_offset_t va;
120         int shmid;
121 };
122
123 static void shm_deallocate_segment(struct shmid_kernel *);
124 static int shm_find_segment_by_key(key_t);
125 static struct shmid_kernel *shm_find_segment_by_shmid(int);
126 static struct shmid_kernel *shm_find_segment_by_shmidx(int);
127 static int shm_delete_mapping(struct vmspace *vm, struct shmmap_state *);
128 static void shmrealloc(void);
129 static int shminit(void);
130 static int sysvshm_modload(struct module *, int, void *);
131 static int shmunload(void);
132 static void shmexit_myhook(struct vmspace *vm);
133 static void shmfork_myhook(struct proc *p1, struct proc *p2);
134 static int sysctl_shmsegs(SYSCTL_HANDLER_ARGS);
135
136 /*
137  * Tuneable values.
138  */
139 #ifndef SHMMAXPGS
140 #define SHMMAXPGS       131072  /* Note: sysv shared memory is swap backed. */
141 #endif
142 #ifndef SHMMAX
143 #define SHMMAX  (SHMMAXPGS*PAGE_SIZE)
144 #endif
145 #ifndef SHMMIN
146 #define SHMMIN  1
147 #endif
148 #ifndef SHMMNI
149 #define SHMMNI  192
150 #endif
151 #ifndef SHMSEG
152 #define SHMSEG  128
153 #endif
154 #ifndef SHMALL
155 #define SHMALL  (SHMMAXPGS)
156 #endif
157
158 struct  shminfo shminfo = {
159         SHMMAX,
160         SHMMIN,
161         SHMMNI,
162         SHMSEG,
163         SHMALL
164 };
165
166 static int shm_use_phys;
167 static int shm_allow_removed;
168
169 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmax, CTLFLAG_RW, &shminfo.shmmax, 0,
170     "Maximum shared memory segment size");
171 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmin, CTLFLAG_RW, &shminfo.shmmin, 0,
172     "Minimum shared memory segment size");
173 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmni, CTLFLAG_RDTUN, &shminfo.shmmni, 0,
174     "Number of shared memory identifiers");
175 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmseg, CTLFLAG_RDTUN, &shminfo.shmseg, 0,
176     "Number of segments per process");
177 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmall, CTLFLAG_RW, &shminfo.shmall, 0,
178     "Maximum number of pages available for shared memory");
179 SYSCTL_INT(_kern_ipc, OID_AUTO, shm_use_phys, CTLFLAG_RW,
180     &shm_use_phys, 0, "Enable/Disable locking of shared memory pages in core");
181 SYSCTL_INT(_kern_ipc, OID_AUTO, shm_allow_removed, CTLFLAG_RW,
182     &shm_allow_removed, 0,
183     "Enable/Disable attachment to attached segments marked for removal");
184 SYSCTL_PROC(_kern_ipc, OID_AUTO, shmsegs, CTLTYPE_OPAQUE | CTLFLAG_RD,
185     NULL, 0, sysctl_shmsegs, "",
186     "Current number of shared memory segments allocated");
187
188 static int
189 shm_find_segment_by_key(key)
190         key_t key;
191 {
192         int i;
193
194         for (i = 0; i < shmalloced; i++)
195                 if ((shmsegs[i].u.shm_perm.mode & SHMSEG_ALLOCATED) &&
196                     shmsegs[i].u.shm_perm.key == key)
197                         return (i);
198         return (-1);
199 }
200
201 static struct shmid_kernel *
202 shm_find_segment_by_shmid(int shmid)
203 {
204         int segnum;
205         struct shmid_kernel *shmseg;
206
207         segnum = IPCID_TO_IX(shmid);
208         if (segnum < 0 || segnum >= shmalloced)
209                 return (NULL);
210         shmseg = &shmsegs[segnum];
211         if ((shmseg->u.shm_perm.mode & SHMSEG_ALLOCATED) == 0 ||
212             (!shm_allow_removed &&
213              (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) != 0) ||
214             shmseg->u.shm_perm.seq != IPCID_TO_SEQ(shmid))
215                 return (NULL);
216         return (shmseg);
217 }
218
219 static struct shmid_kernel *
220 shm_find_segment_by_shmidx(int segnum)
221 {
222         struct shmid_kernel *shmseg;
223
224         if (segnum < 0 || segnum >= shmalloced)
225                 return (NULL);
226         shmseg = &shmsegs[segnum];
227         if ((shmseg->u.shm_perm.mode & SHMSEG_ALLOCATED) == 0 ||
228             (!shm_allow_removed &&
229              (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) != 0))
230                 return (NULL);
231         return (shmseg);
232 }
233
234 static void
235 shm_deallocate_segment(shmseg)
236         struct shmid_kernel *shmseg;
237 {
238         vm_size_t size;
239
240         GIANT_REQUIRED;
241
242         vm_object_deallocate(shmseg->object);
243         shmseg->object = NULL;
244         size = round_page(shmseg->u.shm_segsz);
245         shm_committed -= btoc(size);
246         shm_nused--;
247         shmseg->u.shm_perm.mode = SHMSEG_FREE;
248 #ifdef MAC
249         mac_sysvshm_cleanup(shmseg);
250 #endif
251         racct_sub_cred(shmseg->cred, RACCT_NSHM, 1);
252         racct_sub_cred(shmseg->cred, RACCT_SHMSIZE, size);
253         crfree(shmseg->cred);
254         shmseg->cred = NULL;
255 }
256
257 static int
258 shm_delete_mapping(struct vmspace *vm, struct shmmap_state *shmmap_s)
259 {
260         struct shmid_kernel *shmseg;
261         int segnum, result;
262         vm_size_t size;
263
264         GIANT_REQUIRED;
265
266         segnum = IPCID_TO_IX(shmmap_s->shmid);
267         shmseg = &shmsegs[segnum];
268         size = round_page(shmseg->u.shm_segsz);
269         result = vm_map_remove(&vm->vm_map, shmmap_s->va, shmmap_s->va + size);
270         if (result != KERN_SUCCESS)
271                 return (EINVAL);
272         shmmap_s->shmid = -1;
273         shmseg->u.shm_dtime = time_second;
274         if ((--shmseg->u.shm_nattch <= 0) &&
275             (shmseg->u.shm_perm.mode & SHMSEG_REMOVED)) {
276                 shm_deallocate_segment(shmseg);
277                 shm_last_free = segnum;
278         }
279         return (0);
280 }
281
282 #ifndef _SYS_SYSPROTO_H_
283 struct shmdt_args {
284         const void *shmaddr;
285 };
286 #endif
287 int
288 sys_shmdt(td, uap)
289         struct thread *td;
290         struct shmdt_args *uap;
291 {
292         struct proc *p = td->td_proc;
293         struct shmmap_state *shmmap_s;
294 #ifdef MAC
295         struct shmid_kernel *shmsegptr;
296 #endif
297         int i;
298         int error = 0;
299
300         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
301                 return (ENOSYS);
302         mtx_lock(&Giant);
303         shmmap_s = p->p_vmspace->vm_shm;
304         if (shmmap_s == NULL) {
305                 error = EINVAL;
306                 goto done2;
307         }
308         for (i = 0; i < shminfo.shmseg; i++, shmmap_s++) {
309                 if (shmmap_s->shmid != -1 &&
310                     shmmap_s->va == (vm_offset_t)uap->shmaddr) {
311                         break;
312                 }
313         }
314         if (i == shminfo.shmseg) {
315                 error = EINVAL;
316                 goto done2;
317         }
318 #ifdef MAC
319         shmsegptr = &shmsegs[IPCID_TO_IX(shmmap_s->shmid)];
320         error = mac_sysvshm_check_shmdt(td->td_ucred, shmsegptr);
321         if (error != 0)
322                 goto done2;
323 #endif
324         error = shm_delete_mapping(p->p_vmspace, shmmap_s);
325 done2:
326         mtx_unlock(&Giant);
327         return (error);
328 }
329
330 #ifndef _SYS_SYSPROTO_H_
331 struct shmat_args {
332         int shmid;
333         const void *shmaddr;
334         int shmflg;
335 };
336 #endif
337 int
338 kern_shmat(td, shmid, shmaddr, shmflg)
339         struct thread *td;
340         int shmid;
341         const void *shmaddr;
342         int shmflg;
343 {
344         struct proc *p = td->td_proc;
345         int i;
346         struct shmid_kernel *shmseg;
347         struct shmmap_state *shmmap_s = NULL;
348         vm_offset_t attach_va;
349         vm_prot_t prot;
350         vm_size_t size;
351         int rv;
352         int error = 0;
353
354         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
355                 return (ENOSYS);
356         mtx_lock(&Giant);
357         shmmap_s = p->p_vmspace->vm_shm;
358         if (shmmap_s == NULL) {
359                 shmmap_s = malloc(shminfo.shmseg * sizeof(struct shmmap_state),
360                     M_SHM, M_WAITOK);
361                 for (i = 0; i < shminfo.shmseg; i++)
362                         shmmap_s[i].shmid = -1;
363                 p->p_vmspace->vm_shm = shmmap_s;
364         }
365         shmseg = shm_find_segment_by_shmid(shmid);
366         if (shmseg == NULL) {
367                 error = EINVAL;
368                 goto done2;
369         }
370         error = ipcperm(td, &shmseg->u.shm_perm,
371             (shmflg & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
372         if (error)
373                 goto done2;
374 #ifdef MAC
375         error = mac_sysvshm_check_shmat(td->td_ucred, shmseg, shmflg);
376         if (error != 0)
377                 goto done2;
378 #endif
379         for (i = 0; i < shminfo.shmseg; i++) {
380                 if (shmmap_s->shmid == -1)
381                         break;
382                 shmmap_s++;
383         }
384         if (i >= shminfo.shmseg) {
385                 error = EMFILE;
386                 goto done2;
387         }
388         size = round_page(shmseg->u.shm_segsz);
389         prot = VM_PROT_READ;
390         if ((shmflg & SHM_RDONLY) == 0)
391                 prot |= VM_PROT_WRITE;
392         if (shmaddr) {
393                 if (shmflg & SHM_RND) {
394                         attach_va = (vm_offset_t)shmaddr & ~(SHMLBA-1);
395                 } else if (((vm_offset_t)shmaddr & (SHMLBA-1)) == 0) {
396                         attach_va = (vm_offset_t)shmaddr;
397                 } else {
398                         error = EINVAL;
399                         goto done2;
400                 }
401         } else {
402                 /*
403                  * This is just a hint to vm_map_find() about where to
404                  * put it.
405                  */
406                 PROC_LOCK(p);
407                 attach_va = round_page((vm_offset_t)p->p_vmspace->vm_daddr +
408                     lim_max(p, RLIMIT_DATA));
409                 PROC_UNLOCK(p);
410         }
411
412         vm_object_reference(shmseg->object);
413         rv = vm_map_find(&p->p_vmspace->vm_map, shmseg->object,
414             0, &attach_va, size, 0, shmaddr != NULL ? VMFS_NO_SPACE :
415             VMFS_OPTIMAL_SPACE, prot, prot, MAP_INHERIT_SHARE);
416         if (rv != KERN_SUCCESS) {
417                 vm_object_deallocate(shmseg->object);
418                 error = ENOMEM;
419                 goto done2;
420         }
421
422         shmmap_s->va = attach_va;
423         shmmap_s->shmid = shmid;
424         shmseg->u.shm_lpid = p->p_pid;
425         shmseg->u.shm_atime = time_second;
426         shmseg->u.shm_nattch++;
427         td->td_retval[0] = attach_va;
428 done2:
429         mtx_unlock(&Giant);
430         return (error);
431 }
432
433 int
434 sys_shmat(td, uap)
435         struct thread *td;
436         struct shmat_args *uap;
437 {
438         return kern_shmat(td, uap->shmid, uap->shmaddr, uap->shmflg);
439 }
440
441 int
442 kern_shmctl(td, shmid, cmd, buf, bufsz)
443         struct thread *td;
444         int shmid;
445         int cmd;
446         void *buf;
447         size_t *bufsz;
448 {
449         int error = 0;
450         struct shmid_kernel *shmseg;
451
452         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
453                 return (ENOSYS);
454
455         mtx_lock(&Giant);
456         switch (cmd) {
457         /*
458          * It is possible that kern_shmctl is being called from the Linux ABI
459          * layer, in which case, we will need to implement IPC_INFO.  It should
460          * be noted that other shmctl calls will be funneled through here for
461          * Linix binaries as well.
462          *
463          * NB: The Linux ABI layer will convert this data to structure(s) more
464          * consistent with the Linux ABI.
465          */
466         case IPC_INFO:
467                 memcpy(buf, &shminfo, sizeof(shminfo));
468                 if (bufsz)
469                         *bufsz = sizeof(shminfo);
470                 td->td_retval[0] = shmalloced;
471                 goto done2;
472         case SHM_INFO: {
473                 struct shm_info shm_info;
474                 shm_info.used_ids = shm_nused;
475                 shm_info.shm_rss = 0;   /*XXX where to get from ? */
476                 shm_info.shm_tot = 0;   /*XXX where to get from ? */
477                 shm_info.shm_swp = 0;   /*XXX where to get from ? */
478                 shm_info.swap_attempts = 0;     /*XXX where to get from ? */
479                 shm_info.swap_successes = 0;    /*XXX where to get from ? */
480                 memcpy(buf, &shm_info, sizeof(shm_info));
481                 if (bufsz)
482                         *bufsz = sizeof(shm_info);
483                 td->td_retval[0] = shmalloced;
484                 goto done2;
485         }
486         }
487         if (cmd == SHM_STAT)
488                 shmseg = shm_find_segment_by_shmidx(shmid);
489         else
490                 shmseg = shm_find_segment_by_shmid(shmid);
491         if (shmseg == NULL) {
492                 error = EINVAL;
493                 goto done2;
494         }
495 #ifdef MAC
496         error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, cmd);
497         if (error != 0)
498                 goto done2;
499 #endif
500         switch (cmd) {
501         case SHM_STAT:
502         case IPC_STAT:
503                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
504                 if (error)
505                         goto done2;
506                 memcpy(buf, &shmseg->u, sizeof(struct shmid_ds));
507                 if (bufsz)
508                         *bufsz = sizeof(struct shmid_ds);
509                 if (cmd == SHM_STAT)
510                         td->td_retval[0] = IXSEQ_TO_IPCID(shmid, shmseg->u.shm_perm);
511                 break;
512         case IPC_SET: {
513                 struct shmid_ds *shmid;
514
515                 shmid = (struct shmid_ds *)buf;
516                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
517                 if (error)
518                         goto done2;
519                 shmseg->u.shm_perm.uid = shmid->shm_perm.uid;
520                 shmseg->u.shm_perm.gid = shmid->shm_perm.gid;
521                 shmseg->u.shm_perm.mode =
522                     (shmseg->u.shm_perm.mode & ~ACCESSPERMS) |
523                     (shmid->shm_perm.mode & ACCESSPERMS);
524                 shmseg->u.shm_ctime = time_second;
525                 break;
526         }
527         case IPC_RMID:
528                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
529                 if (error)
530                         goto done2;
531                 shmseg->u.shm_perm.key = IPC_PRIVATE;
532                 shmseg->u.shm_perm.mode |= SHMSEG_REMOVED;
533                 if (shmseg->u.shm_nattch <= 0) {
534                         shm_deallocate_segment(shmseg);
535                         shm_last_free = IPCID_TO_IX(shmid);
536                 }
537                 break;
538 #if 0
539         case SHM_LOCK:
540         case SHM_UNLOCK:
541 #endif
542         default:
543                 error = EINVAL;
544                 break;
545         }
546 done2:
547         mtx_unlock(&Giant);
548         return (error);
549 }
550
551 #ifndef _SYS_SYSPROTO_H_
552 struct shmctl_args {
553         int shmid;
554         int cmd;
555         struct shmid_ds *buf;
556 };
557 #endif
558 int
559 sys_shmctl(td, uap)
560         struct thread *td;
561         struct shmctl_args *uap;
562 {
563         int error = 0;
564         struct shmid_ds buf;
565         size_t bufsz;
566         
567         /*
568          * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
569          * Linux binaries.  If we see the call come through the FreeBSD ABI,
570          * return an error back to the user since we do not to support this.
571          */
572         if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
573             uap->cmd == SHM_STAT)
574                 return (EINVAL);
575
576         /* IPC_SET needs to copyin the buffer before calling kern_shmctl */
577         if (uap->cmd == IPC_SET) {
578                 if ((error = copyin(uap->buf, &buf, sizeof(struct shmid_ds))))
579                         goto done;
580         }
581         
582         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
583         if (error)
584                 goto done;
585         
586         /* Cases in which we need to copyout */
587         switch (uap->cmd) {
588         case IPC_STAT:
589                 error = copyout(&buf, uap->buf, bufsz);
590                 break;
591         }
592
593 done:
594         if (error) {
595                 /* Invalidate the return value */
596                 td->td_retval[0] = -1;
597         }
598         return (error);
599 }
600
601
602 static int
603 shmget_existing(td, uap, mode, segnum)
604         struct thread *td;
605         struct shmget_args *uap;
606         int mode;
607         int segnum;
608 {
609         struct shmid_kernel *shmseg;
610         int error;
611
612         shmseg = &shmsegs[segnum];
613         if (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) {
614                 /*
615                  * This segment is in the process of being allocated.  Wait
616                  * until it's done, and look the key up again (in case the
617                  * allocation failed or it was freed).
618                  */
619                 shmseg->u.shm_perm.mode |= SHMSEG_WANTED;
620                 error = tsleep(shmseg, PLOCK | PCATCH, "shmget", 0);
621                 if (error)
622                         return (error);
623                 return (EAGAIN);
624         }
625         if ((uap->shmflg & (IPC_CREAT | IPC_EXCL)) == (IPC_CREAT | IPC_EXCL))
626                 return (EEXIST);
627 #ifdef MAC
628         error = mac_sysvshm_check_shmget(td->td_ucred, shmseg, uap->shmflg);
629         if (error != 0)
630                 return (error);
631 #endif
632         if (uap->size != 0 && uap->size > shmseg->u.shm_segsz)
633                 return (EINVAL);
634         td->td_retval[0] = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
635         return (0);
636 }
637
638 static int
639 shmget_allocate_segment(td, uap, mode)
640         struct thread *td;
641         struct shmget_args *uap;
642         int mode;
643 {
644         int i, segnum, shmid;
645         size_t size;
646         struct ucred *cred = td->td_ucred;
647         struct shmid_kernel *shmseg;
648         vm_object_t shm_object;
649
650         GIANT_REQUIRED;
651
652         if (uap->size < shminfo.shmmin || uap->size > shminfo.shmmax)
653                 return (EINVAL);
654         if (shm_nused >= shminfo.shmmni) /* Any shmids left? */
655                 return (ENOSPC);
656         size = round_page(uap->size);
657         if (shm_committed + btoc(size) > shminfo.shmall)
658                 return (ENOMEM);
659         if (shm_last_free < 0) {
660                 shmrealloc();   /* Maybe expand the shmsegs[] array. */
661                 for (i = 0; i < shmalloced; i++)
662                         if (shmsegs[i].u.shm_perm.mode & SHMSEG_FREE)
663                                 break;
664                 if (i == shmalloced)
665                         return (ENOSPC);
666                 segnum = i;
667         } else  {
668                 segnum = shm_last_free;
669                 shm_last_free = -1;
670         }
671         shmseg = &shmsegs[segnum];
672 #ifdef RACCT
673         PROC_LOCK(td->td_proc);
674         if (racct_add(td->td_proc, RACCT_NSHM, 1)) {
675                 PROC_UNLOCK(td->td_proc);
676                 return (ENOSPC);
677         }
678         if (racct_add(td->td_proc, RACCT_SHMSIZE, size)) {
679                 racct_sub(td->td_proc, RACCT_NSHM, 1);
680                 PROC_UNLOCK(td->td_proc);
681                 return (ENOMEM);
682         }
683         PROC_UNLOCK(td->td_proc);
684 #endif
685         /*
686          * In case we sleep in malloc(), mark the segment present but deleted
687          * so that noone else tries to create the same key.
688          */
689         shmseg->u.shm_perm.mode = SHMSEG_ALLOCATED | SHMSEG_REMOVED;
690         shmseg->u.shm_perm.key = uap->key;
691         shmseg->u.shm_perm.seq = (shmseg->u.shm_perm.seq + 1) & 0x7fff;
692         shmid = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
693         
694         /*
695          * We make sure that we have allocated a pager before we need
696          * to.
697          */
698         shm_object = vm_pager_allocate(shm_use_phys ? OBJT_PHYS : OBJT_SWAP,
699             0, size, VM_PROT_DEFAULT, 0, cred);
700         if (shm_object == NULL) {
701 #ifdef RACCT
702                 PROC_LOCK(td->td_proc);
703                 racct_sub(td->td_proc, RACCT_NSHM, 1);
704                 racct_sub(td->td_proc, RACCT_SHMSIZE, size);
705                 PROC_UNLOCK(td->td_proc);
706 #endif
707                 return (ENOMEM);
708         }
709         VM_OBJECT_WLOCK(shm_object);
710         vm_object_clear_flag(shm_object, OBJ_ONEMAPPING);
711         vm_object_set_flag(shm_object, OBJ_NOSPLIT);
712         VM_OBJECT_WUNLOCK(shm_object);
713
714         shmseg->object = shm_object;
715         shmseg->u.shm_perm.cuid = shmseg->u.shm_perm.uid = cred->cr_uid;
716         shmseg->u.shm_perm.cgid = shmseg->u.shm_perm.gid = cred->cr_gid;
717         shmseg->u.shm_perm.mode = (shmseg->u.shm_perm.mode & SHMSEG_WANTED) |
718             (mode & ACCESSPERMS) | SHMSEG_ALLOCATED;
719         shmseg->cred = crhold(cred);
720         shmseg->u.shm_segsz = uap->size;
721         shmseg->u.shm_cpid = td->td_proc->p_pid;
722         shmseg->u.shm_lpid = shmseg->u.shm_nattch = 0;
723         shmseg->u.shm_atime = shmseg->u.shm_dtime = 0;
724 #ifdef MAC
725         mac_sysvshm_create(cred, shmseg);
726 #endif
727         shmseg->u.shm_ctime = time_second;
728         shm_committed += btoc(size);
729         shm_nused++;
730         if (shmseg->u.shm_perm.mode & SHMSEG_WANTED) {
731                 /*
732                  * Somebody else wanted this key while we were asleep.  Wake
733                  * them up now.
734                  */
735                 shmseg->u.shm_perm.mode &= ~SHMSEG_WANTED;
736                 wakeup(shmseg);
737         }
738         td->td_retval[0] = shmid;
739         return (0);
740 }
741
742 #ifndef _SYS_SYSPROTO_H_
743 struct shmget_args {
744         key_t key;
745         size_t size;
746         int shmflg;
747 };
748 #endif
749 int
750 sys_shmget(td, uap)
751         struct thread *td;
752         struct shmget_args *uap;
753 {
754         int segnum, mode;
755         int error;
756
757         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
758                 return (ENOSYS);
759         mtx_lock(&Giant);
760         mode = uap->shmflg & ACCESSPERMS;
761         if (uap->key != IPC_PRIVATE) {
762         again:
763                 segnum = shm_find_segment_by_key(uap->key);
764                 if (segnum >= 0) {
765                         error = shmget_existing(td, uap, mode, segnum);
766                         if (error == EAGAIN)
767                                 goto again;
768                         goto done2;
769                 }
770                 if ((uap->shmflg & IPC_CREAT) == 0) {
771                         error = ENOENT;
772                         goto done2;
773                 }
774         }
775         error = shmget_allocate_segment(td, uap, mode);
776 done2:
777         mtx_unlock(&Giant);
778         return (error);
779 }
780
781 static void
782 shmfork_myhook(p1, p2)
783         struct proc *p1, *p2;
784 {
785         struct shmmap_state *shmmap_s;
786         size_t size;
787         int i;
788
789         mtx_lock(&Giant);
790         size = shminfo.shmseg * sizeof(struct shmmap_state);
791         shmmap_s = malloc(size, M_SHM, M_WAITOK);
792         bcopy(p1->p_vmspace->vm_shm, shmmap_s, size);
793         p2->p_vmspace->vm_shm = shmmap_s;
794         for (i = 0; i < shminfo.shmseg; i++, shmmap_s++)
795                 if (shmmap_s->shmid != -1)
796                         shmsegs[IPCID_TO_IX(shmmap_s->shmid)].u.shm_nattch++;
797         mtx_unlock(&Giant);
798 }
799
800 static void
801 shmexit_myhook(struct vmspace *vm)
802 {
803         struct shmmap_state *base, *shm;
804         int i;
805
806         if ((base = vm->vm_shm) != NULL) {
807                 vm->vm_shm = NULL;
808                 mtx_lock(&Giant);
809                 for (i = 0, shm = base; i < shminfo.shmseg; i++, shm++) {
810                         if (shm->shmid != -1)
811                                 shm_delete_mapping(vm, shm);
812                 }
813                 mtx_unlock(&Giant);
814                 free(base, M_SHM);
815         }
816 }
817
818 static void
819 shmrealloc(void)
820 {
821         int i;
822         struct shmid_kernel *newsegs;
823
824         if (shmalloced >= shminfo.shmmni)
825                 return;
826
827         newsegs = malloc(shminfo.shmmni * sizeof(*newsegs), M_SHM, M_WAITOK);
828         if (newsegs == NULL)
829                 return;
830         for (i = 0; i < shmalloced; i++)
831                 bcopy(&shmsegs[i], &newsegs[i], sizeof(newsegs[0]));
832         for (; i < shminfo.shmmni; i++) {
833                 shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
834                 shmsegs[i].u.shm_perm.seq = 0;
835 #ifdef MAC
836                 mac_sysvshm_init(&shmsegs[i]);
837 #endif
838         }
839         free(shmsegs, M_SHM);
840         shmsegs = newsegs;
841         shmalloced = shminfo.shmmni;
842 }
843
844 static struct syscall_helper_data shm_syscalls[] = {
845         SYSCALL_INIT_HELPER(shmat),
846         SYSCALL_INIT_HELPER(shmctl),
847         SYSCALL_INIT_HELPER(shmdt),
848         SYSCALL_INIT_HELPER(shmget),
849 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
850     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
851         SYSCALL_INIT_HELPER_COMPAT(freebsd7_shmctl),
852 #endif
853 #if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
854         SYSCALL_INIT_HELPER(shmsys),
855 #endif
856         SYSCALL_INIT_LAST
857 };
858
859 #ifdef COMPAT_FREEBSD32
860 #include <compat/freebsd32/freebsd32.h>
861 #include <compat/freebsd32/freebsd32_ipc.h>
862 #include <compat/freebsd32/freebsd32_proto.h>
863 #include <compat/freebsd32/freebsd32_signal.h>
864 #include <compat/freebsd32/freebsd32_syscall.h>
865 #include <compat/freebsd32/freebsd32_util.h>
866
867 static struct syscall_helper_data shm32_syscalls[] = {
868         SYSCALL32_INIT_HELPER_COMPAT(shmat),
869         SYSCALL32_INIT_HELPER_COMPAT(shmdt),
870         SYSCALL32_INIT_HELPER_COMPAT(shmget),
871         SYSCALL32_INIT_HELPER(freebsd32_shmsys),
872         SYSCALL32_INIT_HELPER(freebsd32_shmctl),
873 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
874     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
875         SYSCALL32_INIT_HELPER(freebsd7_freebsd32_shmctl),
876 #endif
877         SYSCALL_INIT_LAST
878 };
879 #endif
880
881 static int
882 shminit()
883 {
884         int i, error;
885
886 #ifndef BURN_BRIDGES
887         if (TUNABLE_ULONG_FETCH("kern.ipc.shmmaxpgs", &shminfo.shmall) != 0)
888                 printf("kern.ipc.shmmaxpgs is now called kern.ipc.shmall!\n");
889 #endif
890         TUNABLE_ULONG_FETCH("kern.ipc.shmall", &shminfo.shmall);
891         if (!TUNABLE_ULONG_FETCH("kern.ipc.shmmax", &shminfo.shmmax)) {
892                 /* Initialize shmmax dealing with possible overflow. */
893                 for (i = PAGE_SIZE; i > 0; i--) {
894                         shminfo.shmmax = shminfo.shmall * i;
895                         if (shminfo.shmmax >= shminfo.shmall)
896                                 break;
897                 }
898         }
899         TUNABLE_ULONG_FETCH("kern.ipc.shmmin", &shminfo.shmmin);
900         TUNABLE_ULONG_FETCH("kern.ipc.shmmni", &shminfo.shmmni);
901         TUNABLE_ULONG_FETCH("kern.ipc.shmseg", &shminfo.shmseg);
902         TUNABLE_INT_FETCH("kern.ipc.shm_use_phys", &shm_use_phys);
903
904         shmalloced = shminfo.shmmni;
905         shmsegs = malloc(shmalloced * sizeof(shmsegs[0]), M_SHM, M_WAITOK);
906         for (i = 0; i < shmalloced; i++) {
907                 shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
908                 shmsegs[i].u.shm_perm.seq = 0;
909 #ifdef MAC
910                 mac_sysvshm_init(&shmsegs[i]);
911 #endif
912         }
913         shm_last_free = 0;
914         shm_nused = 0;
915         shm_committed = 0;
916         shmexit_hook = &shmexit_myhook;
917         shmfork_hook = &shmfork_myhook;
918
919         error = syscall_helper_register(shm_syscalls);
920         if (error != 0)
921                 return (error);
922 #ifdef COMPAT_FREEBSD32
923         error = syscall32_helper_register(shm32_syscalls);
924         if (error != 0)
925                 return (error);
926 #endif
927         return (0);
928 }
929
930 static int
931 shmunload()
932 {
933         int i;  
934
935         if (shm_nused > 0)
936                 return (EBUSY);
937
938 #ifdef COMPAT_FREEBSD32
939         syscall32_helper_unregister(shm32_syscalls);
940 #endif
941         syscall_helper_unregister(shm_syscalls);
942
943         for (i = 0; i < shmalloced; i++) {
944 #ifdef MAC
945                 mac_sysvshm_destroy(&shmsegs[i]);
946 #endif
947                 /*
948                  * Objects might be still mapped into the processes
949                  * address spaces.  Actual free would happen on the
950                  * last mapping destruction.
951                  */
952                 if (shmsegs[i].u.shm_perm.mode != SHMSEG_FREE)
953                         vm_object_deallocate(shmsegs[i].object);
954         }
955         free(shmsegs, M_SHM);
956         shmexit_hook = NULL;
957         shmfork_hook = NULL;
958         return (0);
959 }
960
961 static int
962 sysctl_shmsegs(SYSCTL_HANDLER_ARGS)
963 {
964
965         return (SYSCTL_OUT(req, shmsegs, shmalloced * sizeof(shmsegs[0])));
966 }
967
968 #if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
969 struct oshmid_ds {
970         struct  ipc_perm_old shm_perm;  /* operation perms */
971         int     shm_segsz;              /* size of segment (bytes) */
972         u_short shm_cpid;               /* pid, creator */
973         u_short shm_lpid;               /* pid, last operation */
974         short   shm_nattch;             /* no. of current attaches */
975         time_t  shm_atime;              /* last attach time */
976         time_t  shm_dtime;              /* last detach time */
977         time_t  shm_ctime;              /* last change time */
978         void    *shm_handle;            /* internal handle for shm segment */
979 };
980
981 struct oshmctl_args {
982         int shmid;
983         int cmd;
984         struct oshmid_ds *ubuf;
985 };
986
987 static int
988 oshmctl(struct thread *td, struct oshmctl_args *uap)
989 {
990 #ifdef COMPAT_43
991         int error = 0;
992         struct shmid_kernel *shmseg;
993         struct oshmid_ds outbuf;
994
995         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
996                 return (ENOSYS);
997         mtx_lock(&Giant);
998         shmseg = shm_find_segment_by_shmid(uap->shmid);
999         if (shmseg == NULL) {
1000                 error = EINVAL;
1001                 goto done2;
1002         }
1003         switch (uap->cmd) {
1004         case IPC_STAT:
1005                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
1006                 if (error)
1007                         goto done2;
1008 #ifdef MAC
1009                 error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, uap->cmd);
1010                 if (error != 0)
1011                         goto done2;
1012 #endif
1013                 ipcperm_new2old(&shmseg->u.shm_perm, &outbuf.shm_perm);
1014                 outbuf.shm_segsz = shmseg->u.shm_segsz;
1015                 outbuf.shm_cpid = shmseg->u.shm_cpid;
1016                 outbuf.shm_lpid = shmseg->u.shm_lpid;
1017                 outbuf.shm_nattch = shmseg->u.shm_nattch;
1018                 outbuf.shm_atime = shmseg->u.shm_atime;
1019                 outbuf.shm_dtime = shmseg->u.shm_dtime;
1020                 outbuf.shm_ctime = shmseg->u.shm_ctime;
1021                 outbuf.shm_handle = shmseg->object;
1022                 error = copyout(&outbuf, uap->ubuf, sizeof(outbuf));
1023                 if (error)
1024                         goto done2;
1025                 break;
1026         default:
1027                 error = freebsd7_shmctl(td, (struct freebsd7_shmctl_args *)uap);
1028                 break;
1029         }
1030 done2:
1031         mtx_unlock(&Giant);
1032         return (error);
1033 #else
1034         return (EINVAL);
1035 #endif
1036 }
1037
1038 /* XXX casting to (sy_call_t *) is bogus, as usual. */
1039 static sy_call_t *shmcalls[] = {
1040         (sy_call_t *)sys_shmat, (sy_call_t *)oshmctl,
1041         (sy_call_t *)sys_shmdt, (sy_call_t *)sys_shmget,
1042         (sy_call_t *)freebsd7_shmctl
1043 };
1044
1045 int
1046 sys_shmsys(td, uap)
1047         struct thread *td;
1048         /* XXX actually varargs. */
1049         struct shmsys_args /* {
1050                 int     which;
1051                 int     a2;
1052                 int     a3;
1053                 int     a4;
1054         } */ *uap;
1055 {
1056         int error;
1057
1058         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
1059                 return (ENOSYS);
1060         if (uap->which < 0 ||
1061             uap->which >= sizeof(shmcalls)/sizeof(shmcalls[0]))
1062                 return (EINVAL);
1063         mtx_lock(&Giant);
1064         error = (*shmcalls[uap->which])(td, &uap->a2);
1065         mtx_unlock(&Giant);
1066         return (error);
1067 }
1068
1069 #endif  /* i386 && (COMPAT_FREEBSD4 || COMPAT_43) */
1070
1071 #ifdef COMPAT_FREEBSD32
1072
1073 int
1074 freebsd32_shmsys(struct thread *td, struct freebsd32_shmsys_args *uap)
1075 {
1076
1077 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1078     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1079         switch (uap->which) {
1080         case 0: {       /* shmat */
1081                 struct shmat_args ap;
1082
1083                 ap.shmid = uap->a2;
1084                 ap.shmaddr = PTRIN(uap->a3);
1085                 ap.shmflg = uap->a4;
1086                 return (sysent[SYS_shmat].sy_call(td, &ap));
1087         }
1088         case 2: {       /* shmdt */
1089                 struct shmdt_args ap;
1090
1091                 ap.shmaddr = PTRIN(uap->a2);
1092                 return (sysent[SYS_shmdt].sy_call(td, &ap));
1093         }
1094         case 3: {       /* shmget */
1095                 struct shmget_args ap;
1096
1097                 ap.key = uap->a2;
1098                 ap.size = uap->a3;
1099                 ap.shmflg = uap->a4;
1100                 return (sysent[SYS_shmget].sy_call(td, &ap));
1101         }
1102         case 4: {       /* shmctl */
1103                 struct freebsd7_freebsd32_shmctl_args ap;
1104
1105                 ap.shmid = uap->a2;
1106                 ap.cmd = uap->a3;
1107                 ap.buf = PTRIN(uap->a4);
1108                 return (freebsd7_freebsd32_shmctl(td, &ap));
1109         }
1110         case 1:         /* oshmctl */
1111         default:
1112                 return (EINVAL);
1113         }
1114 #else
1115         return (nosys(td, NULL));
1116 #endif
1117 }
1118
1119 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1120     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1121 int
1122 freebsd7_freebsd32_shmctl(struct thread *td,
1123     struct freebsd7_freebsd32_shmctl_args *uap)
1124 {
1125         int error = 0;
1126         union {
1127                 struct shmid_ds shmid_ds;
1128                 struct shm_info shm_info;
1129                 struct shminfo shminfo;
1130         } u;
1131         union {
1132                 struct shmid_ds32_old shmid_ds32;
1133                 struct shm_info32 shm_info32;
1134                 struct shminfo32 shminfo32;
1135         } u32;
1136         size_t sz;
1137
1138         if (uap->cmd == IPC_SET) {
1139                 if ((error = copyin(uap->buf, &u32.shmid_ds32,
1140                     sizeof(u32.shmid_ds32))))
1141                         goto done;
1142                 freebsd32_ipcperm_old_in(&u32.shmid_ds32.shm_perm,
1143                     &u.shmid_ds.shm_perm);
1144                 CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1145                 CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1146                 CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1147                 CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1148                 CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1149                 CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1150                 CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1151         }
1152         
1153         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1154         if (error)
1155                 goto done;
1156         
1157         /* Cases in which we need to copyout */
1158         switch (uap->cmd) {
1159         case IPC_INFO:
1160                 CP(u.shminfo, u32.shminfo32, shmmax);
1161                 CP(u.shminfo, u32.shminfo32, shmmin);
1162                 CP(u.shminfo, u32.shminfo32, shmmni);
1163                 CP(u.shminfo, u32.shminfo32, shmseg);
1164                 CP(u.shminfo, u32.shminfo32, shmall);
1165                 error = copyout(&u32.shminfo32, uap->buf,
1166                     sizeof(u32.shminfo32));
1167                 break;
1168         case SHM_INFO:
1169                 CP(u.shm_info, u32.shm_info32, used_ids);
1170                 CP(u.shm_info, u32.shm_info32, shm_rss);
1171                 CP(u.shm_info, u32.shm_info32, shm_tot);
1172                 CP(u.shm_info, u32.shm_info32, shm_swp);
1173                 CP(u.shm_info, u32.shm_info32, swap_attempts);
1174                 CP(u.shm_info, u32.shm_info32, swap_successes);
1175                 error = copyout(&u32.shm_info32, uap->buf,
1176                     sizeof(u32.shm_info32));
1177                 break;
1178         case SHM_STAT:
1179         case IPC_STAT:
1180                 freebsd32_ipcperm_old_out(&u.shmid_ds.shm_perm,
1181                     &u32.shmid_ds32.shm_perm);
1182                 if (u.shmid_ds.shm_segsz > INT32_MAX)
1183                         u32.shmid_ds32.shm_segsz = INT32_MAX;
1184                 else
1185                         CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1186                 CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1187                 CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1188                 CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1189                 CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1190                 CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1191                 CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1192                 u32.shmid_ds32.shm_internal = 0;
1193                 error = copyout(&u32.shmid_ds32, uap->buf,
1194                     sizeof(u32.shmid_ds32));
1195                 break;
1196         }
1197
1198 done:
1199         if (error) {
1200                 /* Invalidate the return value */
1201                 td->td_retval[0] = -1;
1202         }
1203         return (error);
1204 }
1205 #endif
1206
1207 int
1208 freebsd32_shmctl(struct thread *td, struct freebsd32_shmctl_args *uap)
1209 {
1210         int error = 0;
1211         union {
1212                 struct shmid_ds shmid_ds;
1213                 struct shm_info shm_info;
1214                 struct shminfo shminfo;
1215         } u;
1216         union {
1217                 struct shmid_ds32 shmid_ds32;
1218                 struct shm_info32 shm_info32;
1219                 struct shminfo32 shminfo32;
1220         } u32;
1221         size_t sz;
1222         
1223         if (uap->cmd == IPC_SET) {
1224                 if ((error = copyin(uap->buf, &u32.shmid_ds32,
1225                     sizeof(u32.shmid_ds32))))
1226                         goto done;
1227                 freebsd32_ipcperm_in(&u32.shmid_ds32.shm_perm,
1228                     &u.shmid_ds.shm_perm);
1229                 CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1230                 CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1231                 CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1232                 CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1233                 CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1234                 CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1235                 CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1236         }
1237         
1238         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1239         if (error)
1240                 goto done;
1241         
1242         /* Cases in which we need to copyout */
1243         switch (uap->cmd) {
1244         case IPC_INFO:
1245                 CP(u.shminfo, u32.shminfo32, shmmax);
1246                 CP(u.shminfo, u32.shminfo32, shmmin);
1247                 CP(u.shminfo, u32.shminfo32, shmmni);
1248                 CP(u.shminfo, u32.shminfo32, shmseg);
1249                 CP(u.shminfo, u32.shminfo32, shmall);
1250                 error = copyout(&u32.shminfo32, uap->buf,
1251                     sizeof(u32.shminfo32));
1252                 break;
1253         case SHM_INFO:
1254                 CP(u.shm_info, u32.shm_info32, used_ids);
1255                 CP(u.shm_info, u32.shm_info32, shm_rss);
1256                 CP(u.shm_info, u32.shm_info32, shm_tot);
1257                 CP(u.shm_info, u32.shm_info32, shm_swp);
1258                 CP(u.shm_info, u32.shm_info32, swap_attempts);
1259                 CP(u.shm_info, u32.shm_info32, swap_successes);
1260                 error = copyout(&u32.shm_info32, uap->buf,
1261                     sizeof(u32.shm_info32));
1262                 break;
1263         case SHM_STAT:
1264         case IPC_STAT:
1265                 freebsd32_ipcperm_out(&u.shmid_ds.shm_perm,
1266                     &u32.shmid_ds32.shm_perm);
1267                 if (u.shmid_ds.shm_segsz > INT32_MAX)
1268                         u32.shmid_ds32.shm_segsz = INT32_MAX;
1269                 else
1270                         CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1271                 CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1272                 CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1273                 CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1274                 CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1275                 CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1276                 CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1277                 error = copyout(&u32.shmid_ds32, uap->buf,
1278                     sizeof(u32.shmid_ds32));
1279                 break;
1280         }
1281
1282 done:
1283         if (error) {
1284                 /* Invalidate the return value */
1285                 td->td_retval[0] = -1;
1286         }
1287         return (error);
1288 }
1289 #endif
1290
1291 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1292     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1293
1294 #ifndef CP
1295 #define CP(src, dst, fld)       do { (dst).fld = (src).fld; } while (0)
1296 #endif
1297
1298 #ifndef _SYS_SYSPROTO_H_
1299 struct freebsd7_shmctl_args {
1300         int shmid;
1301         int cmd;
1302         struct shmid_ds_old *buf;
1303 };
1304 #endif
1305 int
1306 freebsd7_shmctl(td, uap)
1307         struct thread *td;
1308         struct freebsd7_shmctl_args *uap;
1309 {
1310         int error = 0;
1311         struct shmid_ds_old old;
1312         struct shmid_ds buf;
1313         size_t bufsz;
1314         
1315         /*
1316          * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
1317          * Linux binaries.  If we see the call come through the FreeBSD ABI,
1318          * return an error back to the user since we do not to support this.
1319          */
1320         if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
1321             uap->cmd == SHM_STAT)
1322                 return (EINVAL);
1323
1324         /* IPC_SET needs to copyin the buffer before calling kern_shmctl */
1325         if (uap->cmd == IPC_SET) {
1326                 if ((error = copyin(uap->buf, &old, sizeof(old))))
1327                         goto done;
1328                 ipcperm_old2new(&old.shm_perm, &buf.shm_perm);
1329                 CP(old, buf, shm_segsz);
1330                 CP(old, buf, shm_lpid);
1331                 CP(old, buf, shm_cpid);
1332                 CP(old, buf, shm_nattch);
1333                 CP(old, buf, shm_atime);
1334                 CP(old, buf, shm_dtime);
1335                 CP(old, buf, shm_ctime);
1336         }
1337         
1338         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
1339         if (error)
1340                 goto done;
1341
1342         /* Cases in which we need to copyout */
1343         switch (uap->cmd) {
1344         case IPC_STAT:
1345                 ipcperm_new2old(&buf.shm_perm, &old.shm_perm);
1346                 if (buf.shm_segsz > INT_MAX)
1347                         old.shm_segsz = INT_MAX;
1348                 else
1349                         CP(buf, old, shm_segsz);
1350                 CP(buf, old, shm_lpid);
1351                 CP(buf, old, shm_cpid);
1352                 if (buf.shm_nattch > SHRT_MAX)
1353                         old.shm_nattch = SHRT_MAX;
1354                 else
1355                         CP(buf, old, shm_nattch);
1356                 CP(buf, old, shm_atime);
1357                 CP(buf, old, shm_dtime);
1358                 CP(buf, old, shm_ctime);
1359                 old.shm_internal = NULL;
1360                 error = copyout(&old, uap->buf, sizeof(old));
1361                 break;
1362         }
1363
1364 done:
1365         if (error) {
1366                 /* Invalidate the return value */
1367                 td->td_retval[0] = -1;
1368         }
1369         return (error);
1370 }
1371
1372 #endif  /* COMPAT_FREEBSD4 || COMPAT_FREEBSD5 || COMPAT_FREEBSD6 ||
1373            COMPAT_FREEBSD7 */
1374
1375 static int
1376 sysvshm_modload(struct module *module, int cmd, void *arg)
1377 {
1378         int error = 0;
1379
1380         switch (cmd) {
1381         case MOD_LOAD:
1382                 error = shminit();
1383                 if (error != 0)
1384                         shmunload();
1385                 break;
1386         case MOD_UNLOAD:
1387                 error = shmunload();
1388                 break;
1389         case MOD_SHUTDOWN:
1390                 break;
1391         default:
1392                 error = EINVAL;
1393                 break;
1394         }
1395         return (error);
1396 }
1397
1398 static moduledata_t sysvshm_mod = {
1399         "sysvshm",
1400         &sysvshm_modload,
1401         NULL
1402 };
1403
1404 DECLARE_MODULE(sysvshm, sysvshm_mod, SI_SUB_SYSV_SHM, SI_ORDER_FIRST);
1405 MODULE_VERSION(sysvshm, 1);