sys/kern/sysv_shm.c

   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/stat.h>
  83 #include <sys/syscall.h>
  84 #include <sys/syscallsubr.h>
  85 #include <sys/sysent.h>
  86 #include <sys/sysproto.h>
  87 #include <sys/jail.h>
  88
  89 #include <security/mac/mac_framework.h>
  90
  91 #include <vm/vm.h>
  92 #include <vm/vm_param.h>
  93 #include <vm/pmap.h>
  94 #include <vm/vm_object.h>
  95 #include <vm/vm_map.h>
  96 #include <vm/vm_page.h>
  97 #include <vm/vm_pager.h>
  98
  99 FEATURE(sysv_shm, "System V shared memory segments support");
 100
 101 static MALLOC_DEFINE(M_SHM, "shm", "SVID compatible shared memory segments");
 102
 103 static int shmget_allocate_segment(struct thread *td,
 104     struct shmget_args *uap, int mode);
 105 static int shmget_existing(struct thread *td, struct shmget_args *uap,
 106     int mode, int segnum);
 107
 108 #define SHMSEG_FREE             0x0200
 109 #define SHMSEG_REMOVED          0x0400
 110 #define SHMSEG_ALLOCATED        0x0800
 111 #define SHMSEG_WANTED           0x1000
 112
 113 static int shm_last_free, shm_nused, shmalloced;
 114 vm_size_t shm_committed;
 115 static struct shmid_kernel      *shmsegs;
 116
 117 struct shmmap_state {
 118         vm_offset_t va;
 119         int shmid;
 120 };
 121
 122 static void shm_deallocate_segment(struct shmid_kernel *);
 123 static int shm_find_segment_by_key(key_t);
 124 static struct shmid_kernel *shm_find_segment_by_shmid(int);
 125 static struct shmid_kernel *shm_find_segment_by_shmidx(int);
 126 static int shm_delete_mapping(struct vmspace *vm, struct shmmap_state *);
 127 static void shmrealloc(void);
 128 static int shminit(void);
 129 static int sysvshm_modload(struct module *, int, void *);
 130 static int shmunload(void);
 131 static void shmexit_myhook(struct vmspace *vm);
 132 static void shmfork_myhook(struct proc *p1, struct proc *p2);
 133 static int sysctl_shmsegs(SYSCTL_HANDLER_ARGS);
 134
 135 /*
 136  * Tuneable values.
 137  */
 138 #ifndef SHMMAXPGS
 139 #define SHMMAXPGS       131072  /* Note: sysv shared memory is swap backed. */
 140 #endif
 141 #ifndef SHMMAX
 142 #define SHMMAX  (SHMMAXPGS*PAGE_SIZE)
 143 #endif
 144 #ifndef SHMMIN
 145 #define SHMMIN  1
 146 #endif
 147 #ifndef SHMMNI
 148 #define SHMMNI  192
 149 #endif
 150 #ifndef SHMSEG
 151 #define SHMSEG  128
 152 #endif
 153 #ifndef SHMALL
 154 #define SHMALL  (SHMMAXPGS)
 155 #endif
 156
 157 struct  shminfo shminfo = {
 158         SHMMAX,
 159         SHMMIN,
 160         SHMMNI,
 161         SHMSEG,
 162         SHMALL
 163 };
 164
 165 static int shm_use_phys;
 166 static int shm_allow_removed;
 167
 168 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmax, CTLFLAG_RW, &shminfo.shmmax, 0,
 169     "Maximum shared memory segment size");
 170 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmin, CTLFLAG_RW, &shminfo.shmmin, 0,
 171     "Minimum shared memory segment size");
 172 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmmni, CTLFLAG_RDTUN, &shminfo.shmmni, 0,
 173     "Number of shared memory identifiers");
 174 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmseg, CTLFLAG_RDTUN, &shminfo.shmseg, 0,
 175     "Number of segments per process");
 176 SYSCTL_ULONG(_kern_ipc, OID_AUTO, shmall, CTLFLAG_RW, &shminfo.shmall, 0,
 177     "Maximum number of pages available for shared memory");
 178 SYSCTL_INT(_kern_ipc, OID_AUTO, shm_use_phys, CTLFLAG_RW,
 179     &shm_use_phys, 0, "Enable/Disable locking of shared memory pages in core");
 180 SYSCTL_INT(_kern_ipc, OID_AUTO, shm_allow_removed, CTLFLAG_RW,
 181     &shm_allow_removed, 0,
 182     "Enable/Disable attachment to attached segments marked for removal");
 183 SYSCTL_PROC(_kern_ipc, OID_AUTO, shmsegs, CTLTYPE_OPAQUE | CTLFLAG_RD,
 184     NULL, 0, sysctl_shmsegs, "",
 185     "Current number of shared memory segments allocated");
 186
 187 static int
 188 shm_find_segment_by_key(key)
 189         key_t key;
 190 {
 191         int i;
 192
 193         for (i = 0; i < shmalloced; i++)
 194                 if ((shmsegs[i].u.shm_perm.mode & SHMSEG_ALLOCATED) &&
 195                     shmsegs[i].u.shm_perm.key == key)
 196                         return (i);
 197         return (-1);
 198 }
 199
 200 static struct shmid_kernel *
 201 shm_find_segment_by_shmid(int shmid)
 202 {
 203         int segnum;
 204         struct shmid_kernel *shmseg;
 205
 206         segnum = IPCID_TO_IX(shmid);
 207         if (segnum < 0 || segnum >= shmalloced)
 208                 return (NULL);
 209         shmseg = &shmsegs[segnum];
 210         if ((shmseg->u.shm_perm.mode & SHMSEG_ALLOCATED) == 0 ||
 211             (!shm_allow_removed &&
 212              (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) != 0) ||
 213             shmseg->u.shm_perm.seq != IPCID_TO_SEQ(shmid))
 214                 return (NULL);
 215         return (shmseg);
 216 }
 217
 218 static struct shmid_kernel *
 219 shm_find_segment_by_shmidx(int segnum)
 220 {
 221         struct shmid_kernel *shmseg;
 222
 223         if (segnum < 0 || segnum >= shmalloced)
 224                 return (NULL);
 225         shmseg = &shmsegs[segnum];
 226         if ((shmseg->u.shm_perm.mode & SHMSEG_ALLOCATED) == 0 ||
 227             (!shm_allow_removed &&
 228              (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) != 0))
 229                 return (NULL);
 230         return (shmseg);
 231 }
 232
 233 static void
 234 shm_deallocate_segment(shmseg)
 235         struct shmid_kernel *shmseg;
 236 {
 237         vm_size_t size;
 238
 239         GIANT_REQUIRED;
 240
 241         vm_object_deallocate(shmseg->object);
 242         shmseg->object = NULL;
 243         size = round_page(shmseg->u.shm_segsz);
 244         shm_committed -= btoc(size);
 245         shm_nused--;
 246         shmseg->u.shm_perm.mode = SHMSEG_FREE;
 247 #ifdef MAC
 248         mac_sysvshm_cleanup(shmseg);
 249 #endif
 250         racct_sub_cred(shmseg->cred, RACCT_NSHM, 1);
 251         racct_sub_cred(shmseg->cred, RACCT_SHMSIZE, size);
 252         crfree(shmseg->cred);
 253         shmseg->cred = NULL;
 254 }
 255
 256 static int
 257 shm_delete_mapping(struct vmspace *vm, struct shmmap_state *shmmap_s)
 258 {
 259         struct shmid_kernel *shmseg;
 260         int segnum, result;
 261         vm_size_t size;
 262
 263         GIANT_REQUIRED;
 264
 265         segnum = IPCID_TO_IX(shmmap_s->shmid);
 266         shmseg = &shmsegs[segnum];
 267         size = round_page(shmseg->u.shm_segsz);
 268         result = vm_map_remove(&vm->vm_map, shmmap_s->va, shmmap_s->va + size);
 269         if (result != KERN_SUCCESS)
 270                 return (EINVAL);
 271         shmmap_s->shmid = -1;
 272         shmseg->u.shm_dtime = time_second;
 273         if ((--shmseg->u.shm_nattch <= 0) &&
 274             (shmseg->u.shm_perm.mode & SHMSEG_REMOVED)) {
 275                 shm_deallocate_segment(shmseg);
 276                 shm_last_free = segnum;
 277         }
 278         return (0);
 279 }
 280
 281 #ifndef _SYS_SYSPROTO_H_
 282 struct shmdt_args {
 283         const void *shmaddr;
 284 };
 285 #endif
 286 int
 287 sys_shmdt(td, uap)
 288         struct thread *td;
 289         struct shmdt_args *uap;
 290 {
 291         struct proc *p = td->td_proc;
 292         struct shmmap_state *shmmap_s;
 293 #ifdef MAC
 294         struct shmid_kernel *shmsegptr;
 295 #endif
 296         int i;
 297         int error = 0;
 298
 299         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
 300                 return (ENOSYS);
 301         mtx_lock(&Giant);
 302         shmmap_s = p->p_vmspace->vm_shm;
 303         if (shmmap_s == NULL) {
 304                 error = EINVAL;
 305                 goto done2;
 306         }
 307         for (i = 0; i < shminfo.shmseg; i++, shmmap_s++) {
 308                 if (shmmap_s->shmid != -1 &&
 309                     shmmap_s->va == (vm_offset_t)uap->shmaddr) {
 310                         break;
 311                 }
 312         }
 313         if (i == shminfo.shmseg) {
 314                 error = EINVAL;
 315                 goto done2;
 316         }
 317 #ifdef MAC
 318         shmsegptr = &shmsegs[IPCID_TO_IX(shmmap_s->shmid)];
 319         error = mac_sysvshm_check_shmdt(td->td_ucred, shmsegptr);
 320         if (error != 0)
 321                 goto done2;
 322 #endif
 323         error = shm_delete_mapping(p->p_vmspace, shmmap_s);
 324 done2:
 325         mtx_unlock(&Giant);
 326         return (error);
 327 }
 328
 329 #ifndef _SYS_SYSPROTO_H_
 330 struct shmat_args {
 331         int shmid;
 332         const void *shmaddr;
 333         int shmflg;
 334 };
 335 #endif
 336 int
 337 kern_shmat(td, shmid, shmaddr, shmflg)
 338         struct thread *td;
 339         int shmid;
 340         const void *shmaddr;
 341         int shmflg;
 342 {
 343         struct proc *p = td->td_proc;
 344         int i, flags;
 345         struct shmid_kernel *shmseg;
 346         struct shmmap_state *shmmap_s = NULL;
 347         vm_offset_t attach_va;
 348         vm_prot_t prot;
 349         vm_size_t size;
 350         int rv;
 351         int error = 0;
 352
 353         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
 354                 return (ENOSYS);
 355         mtx_lock(&Giant);
 356         shmmap_s = p->p_vmspace->vm_shm;
 357         if (shmmap_s == NULL) {
 358                 shmmap_s = malloc(shminfo.shmseg * sizeof(struct shmmap_state),
 359                     M_SHM, M_WAITOK);
 360                 for (i = 0; i < shminfo.shmseg; i++)
 361                         shmmap_s[i].shmid = -1;
 362                 p->p_vmspace->vm_shm = shmmap_s;
 363         }
 364         shmseg = shm_find_segment_by_shmid(shmid);
 365         if (shmseg == NULL) {
 366                 error = EINVAL;
 367                 goto done2;
 368         }
 369         error = ipcperm(td, &shmseg->u.shm_perm,
 370             (shmflg & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
 371         if (error)
 372                 goto done2;
 373 #ifdef MAC
 374         error = mac_sysvshm_check_shmat(td->td_ucred, shmseg, shmflg);
 375         if (error != 0)
 376                 goto done2;
 377 #endif
 378         for (i = 0; i < shminfo.shmseg; i++) {
 379                 if (shmmap_s->shmid == -1)
 380                         break;
 381                 shmmap_s++;
 382         }
 383         if (i >= shminfo.shmseg) {
 384                 error = EMFILE;
 385                 goto done2;
 386         }
 387         size = round_page(shmseg->u.shm_segsz);
 388         prot = VM_PROT_READ;
 389         if ((shmflg & SHM_RDONLY) == 0)
 390                 prot |= VM_PROT_WRITE;
 391         flags = MAP_ANON | MAP_SHARED;
 392         if (shmaddr) {
 393                 flags |= MAP_FIXED;
 394                 if (shmflg & SHM_RND) {
 395                         attach_va = (vm_offset_t)shmaddr & ~(SHMLBA-1);
 396                 } else if (((vm_offset_t)shmaddr & (SHMLBA-1)) == 0) {
 397                         attach_va = (vm_offset_t)shmaddr;
 398                 } else {
 399                         error = EINVAL;
 400                         goto done2;
 401                 }
 402         } else {
 403                 /*
 404                  * This is just a hint to vm_map_find() about where to
 405                  * put it.
 406                  */
 407                 PROC_LOCK(p);
 408                 attach_va = round_page((vm_offset_t)p->p_vmspace->vm_daddr +
 409                     lim_max(p, RLIMIT_DATA));
 410                 PROC_UNLOCK(p);
 411         }
 412
 413         vm_object_reference(shmseg->object);
 414         rv = vm_map_find(&p->p_vmspace->vm_map, shmseg->object,
 415             0, &attach_va, size, (flags & MAP_FIXED) ? VMFS_NO_SPACE :
 416             VMFS_ANY_SPACE, prot, prot, 0);
 417         if (rv != KERN_SUCCESS) {
 418                 vm_object_deallocate(shmseg->object);
 419                 error = ENOMEM;
 420                 goto done2;
 421         }
 422         vm_map_inherit(&p->p_vmspace->vm_map,
 423                 attach_va, attach_va + size, VM_INHERIT_SHARE);
 424
 425         shmmap_s->va = attach_va;
 426         shmmap_s->shmid = shmid;
 427         shmseg->u.shm_lpid = p->p_pid;
 428         shmseg->u.shm_atime = time_second;
 429         shmseg->u.shm_nattch++;
 430         td->td_retval[0] = attach_va;
 431 done2:
 432         mtx_unlock(&Giant);
 433         return (error);
 434 }
 435
 436 int
 437 sys_shmat(td, uap)
 438         struct thread *td;
 439         struct shmat_args *uap;
 440 {
 441         return kern_shmat(td, uap->shmid, uap->shmaddr, uap->shmflg);
 442 }
 443
 444 int
 445 kern_shmctl(td, shmid, cmd, buf, bufsz)
 446         struct thread *td;
 447         int shmid;
 448         int cmd;
 449         void *buf;
 450         size_t *bufsz;
 451 {
 452         int error = 0;
 453         struct shmid_kernel *shmseg;
 454
 455         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
 456                 return (ENOSYS);
 457
 458         mtx_lock(&Giant);
 459         switch (cmd) {
 460         /*
 461          * It is possible that kern_shmctl is being called from the Linux ABI
 462          * layer, in which case, we will need to implement IPC_INFO.  It should
 463          * be noted that other shmctl calls will be funneled through here for
 464          * Linix binaries as well.
 465          *
 466          * NB: The Linux ABI layer will convert this data to structure(s) more
 467          * consistent with the Linux ABI.
 468          */
 469         case IPC_INFO:
 470                 memcpy(buf, &shminfo, sizeof(shminfo));
 471                 if (bufsz)
 472                         *bufsz = sizeof(shminfo);
 473                 td->td_retval[0] = shmalloced;
 474                 goto done2;
 475         case SHM_INFO: {
 476                 struct shm_info shm_info;
 477                 shm_info.used_ids = shm_nused;
 478                 shm_info.shm_rss = 0;   /*XXX where to get from ? */
 479                 shm_info.shm_tot = 0;   /*XXX where to get from ? */
 480                 shm_info.shm_swp = 0;   /*XXX where to get from ? */
 481                 shm_info.swap_attempts = 0;     /*XXX where to get from ? */
 482                 shm_info.swap_successes = 0;    /*XXX where to get from ? */
 483                 memcpy(buf, &shm_info, sizeof(shm_info));
 484                 if (bufsz)
 485                         *bufsz = sizeof(shm_info);
 486                 td->td_retval[0] = shmalloced;
 487                 goto done2;
 488         }
 489         }
 490         if (cmd == SHM_STAT)
 491                 shmseg = shm_find_segment_by_shmidx(shmid);
 492         else
 493                 shmseg = shm_find_segment_by_shmid(shmid);
 494         if (shmseg == NULL) {
 495                 error = EINVAL;
 496                 goto done2;
 497         }
 498 #ifdef MAC
 499         error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, cmd);
 500         if (error != 0)
 501                 goto done2;
 502 #endif
 503         switch (cmd) {
 504         case SHM_STAT:
 505         case IPC_STAT:
 506                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
 507                 if (error)
 508                         goto done2;
 509                 memcpy(buf, &shmseg->u, sizeof(struct shmid_ds));
 510                 if (bufsz)
 511                         *bufsz = sizeof(struct shmid_ds);
 512                 if (cmd == SHM_STAT)
 513                         td->td_retval[0] = IXSEQ_TO_IPCID(shmid, shmseg->u.shm_perm);
 514                 break;
 515         case IPC_SET: {
 516                 struct shmid_ds *shmid;
 517
 518                 shmid = (struct shmid_ds *)buf;
 519                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
 520                 if (error)
 521                         goto done2;
 522                 shmseg->u.shm_perm.uid = shmid->shm_perm.uid;
 523                 shmseg->u.shm_perm.gid = shmid->shm_perm.gid;
 524                 shmseg->u.shm_perm.mode =
 525                     (shmseg->u.shm_perm.mode & ~ACCESSPERMS) |
 526                     (shmid->shm_perm.mode & ACCESSPERMS);
 527                 shmseg->u.shm_ctime = time_second;
 528                 break;
 529         }
 530         case IPC_RMID:
 531                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_M);
 532                 if (error)
 533                         goto done2;
 534                 shmseg->u.shm_perm.key = IPC_PRIVATE;
 535                 shmseg->u.shm_perm.mode |= SHMSEG_REMOVED;
 536                 if (shmseg->u.shm_nattch <= 0) {
 537                         shm_deallocate_segment(shmseg);
 538                         shm_last_free = IPCID_TO_IX(shmid);
 539                 }
 540                 break;
 541 #if 0
 542         case SHM_LOCK:
 543         case SHM_UNLOCK:
 544 #endif
 545         default:
 546                 error = EINVAL;
 547                 break;
 548         }
 549 done2:
 550         mtx_unlock(&Giant);
 551         return (error);
 552 }
 553
 554 #ifndef _SYS_SYSPROTO_H_
 555 struct shmctl_args {
 556         int shmid;
 557         int cmd;
 558         struct shmid_ds *buf;
 559 };
 560 #endif
 561 int
 562 sys_shmctl(td, uap)
 563         struct thread *td;
 564         struct shmctl_args *uap;
 565 {
 566         int error = 0;
 567         struct shmid_ds buf;
 568         size_t bufsz;
 569
 570         /*
 571          * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
 572          * Linux binaries.  If we see the call come through the FreeBSD ABI,
 573          * return an error back to the user since we do not to support this.
 574          */
 575         if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
 576             uap->cmd == SHM_STAT)
 577                 return (EINVAL);
 578
 579         /* IPC_SET needs to copyin the buffer before calling kern_shmctl */
 580         if (uap->cmd == IPC_SET) {
 581                 if ((error = copyin(uap->buf, &buf, sizeof(struct shmid_ds))))
 582                         goto done;
 583         }
 584
 585         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
 586         if (error)
 587                 goto done;
 588
 589         /* Cases in which we need to copyout */
 590         switch (uap->cmd) {
 591         case IPC_STAT:
 592                 error = copyout(&buf, uap->buf, bufsz);
 593                 break;
 594         }
 595
 596 done:
 597         if (error) {
 598                 /* Invalidate the return value */
 599                 td->td_retval[0] = -1;
 600         }
 601         return (error);
 602 }
 603
 604
 605 static int
 606 shmget_existing(td, uap, mode, segnum)
 607         struct thread *td;
 608         struct shmget_args *uap;
 609         int mode;
 610         int segnum;
 611 {
 612         struct shmid_kernel *shmseg;
 613         int error;
 614
 615         shmseg = &shmsegs[segnum];
 616         if (shmseg->u.shm_perm.mode & SHMSEG_REMOVED) {
 617                 /*
 618                  * This segment is in the process of being allocated.  Wait
 619                  * until it's done, and look the key up again (in case the
 620                  * allocation failed or it was freed).
 621                  */
 622                 shmseg->u.shm_perm.mode |= SHMSEG_WANTED;
 623                 error = tsleep(shmseg, PLOCK | PCATCH, "shmget", 0);
 624                 if (error)
 625                         return (error);
 626                 return (EAGAIN);
 627         }
 628         if ((uap->shmflg & (IPC_CREAT | IPC_EXCL)) == (IPC_CREAT | IPC_EXCL))
 629                 return (EEXIST);
 630 #ifdef MAC
 631         error = mac_sysvshm_check_shmget(td->td_ucred, shmseg, uap->shmflg);
 632         if (error != 0)
 633                 return (error);
 634 #endif
 635         if (uap->size != 0 && uap->size > shmseg->u.shm_segsz)
 636                 return (EINVAL);
 637         td->td_retval[0] = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
 638         return (0);
 639 }
 640
 641 static int
 642 shmget_allocate_segment(td, uap, mode)
 643         struct thread *td;
 644         struct shmget_args *uap;
 645         int mode;
 646 {
 647         int i, segnum, shmid;
 648         size_t size;
 649         struct ucred *cred = td->td_ucred;
 650         struct shmid_kernel *shmseg;
 651         vm_object_t shm_object;
 652
 653         GIANT_REQUIRED;
 654
 655         if (uap->size < shminfo.shmmin || uap->size > shminfo.shmmax)
 656                 return (EINVAL);
 657         if (shm_nused >= shminfo.shmmni) /* Any shmids left? */
 658                 return (ENOSPC);
 659         size = round_page(uap->size);
 660         if (shm_committed + btoc(size) > shminfo.shmall)
 661                 return (ENOMEM);
 662         if (shm_last_free < 0) {
 663                 shmrealloc();   /* Maybe expand the shmsegs[] array. */
 664                 for (i = 0; i < shmalloced; i++)
 665                         if (shmsegs[i].u.shm_perm.mode & SHMSEG_FREE)
 666                                 break;
 667                 if (i == shmalloced)
 668                         return (ENOSPC);
 669                 segnum = i;
 670         } else  {
 671                 segnum = shm_last_free;
 672                 shm_last_free = -1;
 673         }
 674         shmseg = &shmsegs[segnum];
 675 #ifdef RACCT
 676         PROC_LOCK(td->td_proc);
 677         if (racct_add(td->td_proc, RACCT_NSHM, 1)) {
 678                 PROC_UNLOCK(td->td_proc);
 679                 return (ENOSPC);
 680         }
 681         if (racct_add(td->td_proc, RACCT_SHMSIZE, size)) {
 682                 racct_sub(td->td_proc, RACCT_NSHM, 1);
 683                 PROC_UNLOCK(td->td_proc);
 684                 return (ENOMEM);
 685         }
 686         PROC_UNLOCK(td->td_proc);
 687 #endif
 688         /*
 689          * In case we sleep in malloc(), mark the segment present but deleted
 690          * so that noone else tries to create the same key.
 691          */
 692         shmseg->u.shm_perm.mode = SHMSEG_ALLOCATED | SHMSEG_REMOVED;
 693         shmseg->u.shm_perm.key = uap->key;
 694         shmseg->u.shm_perm.seq = (shmseg->u.shm_perm.seq + 1) & 0x7fff;
 695         shmid = IXSEQ_TO_IPCID(segnum, shmseg->u.shm_perm);
 696
 697         /*
 698          * We make sure that we have allocated a pager before we need
 699          * to.
 700          */
 701         shm_object = vm_pager_allocate(shm_use_phys ? OBJT_PHYS : OBJT_SWAP,
 702             0, size, VM_PROT_DEFAULT, 0, cred);
 703         if (shm_object == NULL) {
 704 #ifdef RACCT
 705                 PROC_LOCK(td->td_proc);
 706                 racct_sub(td->td_proc, RACCT_NSHM, 1);
 707                 racct_sub(td->td_proc, RACCT_SHMSIZE, size);
 708                 PROC_UNLOCK(td->td_proc);
 709 #endif
 710                 return (ENOMEM);
 711         }
 712         VM_OBJECT_LOCK(shm_object);
 713         vm_object_clear_flag(shm_object, OBJ_ONEMAPPING);
 714         vm_object_set_flag(shm_object, OBJ_NOSPLIT);
 715         VM_OBJECT_UNLOCK(shm_object);
 716
 717         shmseg->object = shm_object;
 718         shmseg->u.shm_perm.cuid = shmseg->u.shm_perm.uid = cred->cr_uid;
 719         shmseg->u.shm_perm.cgid = shmseg->u.shm_perm.gid = cred->cr_gid;
 720         shmseg->u.shm_perm.mode = (shmseg->u.shm_perm.mode & SHMSEG_WANTED) |
 721             (mode & ACCESSPERMS) | SHMSEG_ALLOCATED;
 722         shmseg->cred = crhold(cred);
 723         shmseg->u.shm_segsz = uap->size;
 724         shmseg->u.shm_cpid = td->td_proc->p_pid;
 725         shmseg->u.shm_lpid = shmseg->u.shm_nattch = 0;
 726         shmseg->u.shm_atime = shmseg->u.shm_dtime = 0;
 727 #ifdef MAC
 728         mac_sysvshm_create(cred, shmseg);
 729 #endif
 730         shmseg->u.shm_ctime = time_second;
 731         shm_committed += btoc(size);
 732         shm_nused++;
 733         if (shmseg->u.shm_perm.mode & SHMSEG_WANTED) {
 734                 /*
 735                  * Somebody else wanted this key while we were asleep.  Wake
 736                  * them up now.
 737                  */
 738                 shmseg->u.shm_perm.mode &= ~SHMSEG_WANTED;
 739                 wakeup(shmseg);
 740         }
 741         td->td_retval[0] = shmid;
 742         return (0);
 743 }
 744
 745 #ifndef _SYS_SYSPROTO_H_
 746 struct shmget_args {
 747         key_t key;
 748         size_t size;
 749         int shmflg;
 750 };
 751 #endif
 752 int
 753 sys_shmget(td, uap)
 754         struct thread *td;
 755         struct shmget_args *uap;
 756 {
 757         int segnum, mode;
 758         int error;
 759
 760         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
 761                 return (ENOSYS);
 762         mtx_lock(&Giant);
 763         mode = uap->shmflg & ACCESSPERMS;
 764         if (uap->key != IPC_PRIVATE) {
 765         again:
 766                 segnum = shm_find_segment_by_key(uap->key);
 767                 if (segnum >= 0) {
 768                         error = shmget_existing(td, uap, mode, segnum);
 769                         if (error == EAGAIN)
 770                                 goto again;
 771                         goto done2;
 772                 }
 773                 if ((uap->shmflg & IPC_CREAT) == 0) {
 774                         error = ENOENT;
 775                         goto done2;
 776                 }
 777         }
 778         error = shmget_allocate_segment(td, uap, mode);
 779 done2:
 780         mtx_unlock(&Giant);
 781         return (error);
 782 }
 783
 784 static void
 785 shmfork_myhook(p1, p2)
 786         struct proc *p1, *p2;
 787 {
 788         struct shmmap_state *shmmap_s;
 789         size_t size;
 790         int i;
 791
 792         mtx_lock(&Giant);
 793         size = shminfo.shmseg * sizeof(struct shmmap_state);
 794         shmmap_s = malloc(size, M_SHM, M_WAITOK);
 795         bcopy(p1->p_vmspace->vm_shm, shmmap_s, size);
 796         p2->p_vmspace->vm_shm = shmmap_s;
 797         for (i = 0; i < shminfo.shmseg; i++, shmmap_s++)
 798                 if (shmmap_s->shmid != -1)
 799                         shmsegs[IPCID_TO_IX(shmmap_s->shmid)].u.shm_nattch++;
 800         mtx_unlock(&Giant);
 801 }
 802
 803 static void
 804 shmexit_myhook(struct vmspace *vm)
 805 {
 806         struct shmmap_state *base, *shm;
 807         int i;
 808
 809         if ((base = vm->vm_shm) != NULL) {
 810                 vm->vm_shm = NULL;
 811                 mtx_lock(&Giant);
 812                 for (i = 0, shm = base; i < shminfo.shmseg; i++, shm++) {
 813                         if (shm->shmid != -1)
 814                                 shm_delete_mapping(vm, shm);
 815                 }
 816                 mtx_unlock(&Giant);
 817                 free(base, M_SHM);
 818         }
 819 }
 820
 821 static void
 822 shmrealloc(void)
 823 {
 824         int i;
 825         struct shmid_kernel *newsegs;
 826
 827         if (shmalloced >= shminfo.shmmni)
 828                 return;
 829
 830         newsegs = malloc(shminfo.shmmni * sizeof(*newsegs), M_SHM, M_WAITOK);
 831         if (newsegs == NULL)
 832                 return;
 833         for (i = 0; i < shmalloced; i++)
 834                 bcopy(&shmsegs[i], &newsegs[i], sizeof(newsegs[0]));
 835         for (; i < shminfo.shmmni; i++) {
 836                 shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
 837                 shmsegs[i].u.shm_perm.seq = 0;
 838 #ifdef MAC
 839                 mac_sysvshm_init(&shmsegs[i]);
 840 #endif
 841         }
 842         free(shmsegs, M_SHM);
 843         shmsegs = newsegs;
 844         shmalloced = shminfo.shmmni;
 845 }
 846
 847 static struct syscall_helper_data shm_syscalls[] = {
 848         SYSCALL_INIT_HELPER(shmat),
 849         SYSCALL_INIT_HELPER(shmctl),
 850         SYSCALL_INIT_HELPER(shmdt),
 851         SYSCALL_INIT_HELPER(shmget),
 852 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
 853     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
 854         SYSCALL_INIT_HELPER_COMPAT(freebsd7_shmctl),
 855 #endif
 856 #if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
 857         SYSCALL_INIT_HELPER(shmsys),
 858 #endif
 859         SYSCALL_INIT_LAST
 860 };
 861
 862 #ifdef COMPAT_FREEBSD32
 863 #include <compat/freebsd32/freebsd32.h>
 864 #include <compat/freebsd32/freebsd32_ipc.h>
 865 #include <compat/freebsd32/freebsd32_proto.h>
 866 #include <compat/freebsd32/freebsd32_signal.h>
 867 #include <compat/freebsd32/freebsd32_syscall.h>
 868 #include <compat/freebsd32/freebsd32_util.h>
 869
 870 static struct syscall_helper_data shm32_syscalls[] = {
 871         SYSCALL32_INIT_HELPER_COMPAT(shmat),
 872         SYSCALL32_INIT_HELPER_COMPAT(shmdt),
 873         SYSCALL32_INIT_HELPER_COMPAT(shmget),
 874         SYSCALL32_INIT_HELPER(freebsd32_shmsys),
 875         SYSCALL32_INIT_HELPER(freebsd32_shmctl),
 876 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
 877     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
 878         SYSCALL32_INIT_HELPER(freebsd7_freebsd32_shmctl),
 879 #endif
 880         SYSCALL_INIT_LAST
 881 };
 882 #endif
 883
 884 static int
 885 shminit()
 886 {
 887         int i, error;
 888
 889 #ifndef BURN_BRIDGES
 890         if (TUNABLE_ULONG_FETCH("kern.ipc.shmmaxpgs", &shminfo.shmall) != 0)
 891                 printf("kern.ipc.shmmaxpgs is now called kern.ipc.shmall!\n");
 892 #endif
 893         TUNABLE_ULONG_FETCH("kern.ipc.shmall", &shminfo.shmall);
 894
 895         /* Initialize shmmax dealing with possible overflow. */
 896         for (i = PAGE_SIZE; i > 0; i--) {
 897                 shminfo.shmmax = shminfo.shmall * i;
 898                 if (shminfo.shmmax >= shminfo.shmall)
 899                         break;
 900         }
 901
 902         TUNABLE_ULONG_FETCH("kern.ipc.shmmin", &shminfo.shmmin);
 903         TUNABLE_ULONG_FETCH("kern.ipc.shmmni", &shminfo.shmmni);
 904         TUNABLE_ULONG_FETCH("kern.ipc.shmseg", &shminfo.shmseg);
 905         TUNABLE_INT_FETCH("kern.ipc.shm_use_phys", &shm_use_phys);
 906
 907         shmalloced = shminfo.shmmni;
 908         shmsegs = malloc(shmalloced * sizeof(shmsegs[0]), M_SHM, M_WAITOK);
 909         for (i = 0; i < shmalloced; i++) {
 910                 shmsegs[i].u.shm_perm.mode = SHMSEG_FREE;
 911                 shmsegs[i].u.shm_perm.seq = 0;
 912 #ifdef MAC
 913                 mac_sysvshm_init(&shmsegs[i]);
 914 #endif
 915         }
 916         shm_last_free = 0;
 917         shm_nused = 0;
 918         shm_committed = 0;
 919         shmexit_hook = &shmexit_myhook;
 920         shmfork_hook = &shmfork_myhook;
 921
 922         error = syscall_helper_register(shm_syscalls);
 923         if (error != 0)
 924                 return (error);
 925 #ifdef COMPAT_FREEBSD32
 926         error = syscall32_helper_register(shm32_syscalls);
 927         if (error != 0)
 928                 return (error);
 929 #endif
 930         return (0);
 931 }
 932
 933 static int
 934 shmunload()
 935 {
 936         int i;
 937
 938         if (shm_nused > 0)
 939                 return (EBUSY);
 940
 941 #ifdef COMPAT_FREEBSD32
 942         syscall32_helper_unregister(shm32_syscalls);
 943 #endif
 944         syscall_helper_unregister(shm_syscalls);
 945
 946         for (i = 0; i < shmalloced; i++) {
 947 #ifdef MAC
 948                 mac_sysvshm_destroy(&shmsegs[i]);
 949 #endif
 950                 /*
 951                  * Objects might be still mapped into the processes
 952                  * address spaces.  Actual free would happen on the
 953                  * last mapping destruction.
 954                  */
 955                 if (shmsegs[i].u.shm_perm.mode != SHMSEG_FREE)
 956                         vm_object_deallocate(shmsegs[i].object);
 957         }
 958         free(shmsegs, M_SHM);
 959         shmexit_hook = NULL;
 960         shmfork_hook = NULL;
 961         return (0);
 962 }
 963
 964 static int
 965 sysctl_shmsegs(SYSCTL_HANDLER_ARGS)
 966 {
 967
 968         return (SYSCTL_OUT(req, shmsegs, shmalloced * sizeof(shmsegs[0])));
 969 }
 970
 971 #if defined(__i386__) && (defined(COMPAT_FREEBSD4) || defined(COMPAT_43))
 972 struct oshmid_ds {
 973         struct  ipc_perm_old shm_perm;  /* operation perms */
 974         int     shm_segsz;              /* size of segment (bytes) */
 975         u_short shm_cpid;               /* pid, creator */
 976         u_short shm_lpid;               /* pid, last operation */
 977         short   shm_nattch;             /* no. of current attaches */
 978         time_t  shm_atime;              /* last attach time */
 979         time_t  shm_dtime;              /* last detach time */
 980         time_t  shm_ctime;              /* last change time */
 981         void    *shm_handle;            /* internal handle for shm segment */
 982 };
 983
 984 struct oshmctl_args {
 985         int shmid;
 986         int cmd;
 987         struct oshmid_ds *ubuf;
 988 };
 989
 990 static int
 991 oshmctl(struct thread *td, struct oshmctl_args *uap)
 992 {
 993 #ifdef COMPAT_43
 994         int error = 0;
 995         struct shmid_kernel *shmseg;
 996         struct oshmid_ds outbuf;
 997
 998         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
 999                 return (ENOSYS);
1000         mtx_lock(&Giant);
1001         shmseg = shm_find_segment_by_shmid(uap->shmid);
1002         if (shmseg == NULL) {
1003                 error = EINVAL;
1004                 goto done2;
1005         }
1006         switch (uap->cmd) {
1007         case IPC_STAT:
1008                 error = ipcperm(td, &shmseg->u.shm_perm, IPC_R);
1009                 if (error)
1010                         goto done2;
1011 #ifdef MAC
1012                 error = mac_sysvshm_check_shmctl(td->td_ucred, shmseg, uap->cmd);
1013                 if (error != 0)
1014                         goto done2;
1015 #endif
1016                 ipcperm_new2old(&shmseg->u.shm_perm, &outbuf.shm_perm);
1017                 outbuf.shm_segsz = shmseg->u.shm_segsz;
1018                 outbuf.shm_cpid = shmseg->u.shm_cpid;
1019                 outbuf.shm_lpid = shmseg->u.shm_lpid;
1020                 outbuf.shm_nattch = shmseg->u.shm_nattch;
1021                 outbuf.shm_atime = shmseg->u.shm_atime;
1022                 outbuf.shm_dtime = shmseg->u.shm_dtime;
1023                 outbuf.shm_ctime = shmseg->u.shm_ctime;
1024                 outbuf.shm_handle = shmseg->object;
1025                 error = copyout(&outbuf, uap->ubuf, sizeof(outbuf));
1026                 if (error)
1027                         goto done2;
1028                 break;
1029         default:
1030                 error = freebsd7_shmctl(td, (struct freebsd7_shmctl_args *)uap);
1031                 break;
1032         }
1033 done2:
1034         mtx_unlock(&Giant);
1035         return (error);
1036 #else
1037         return (EINVAL);
1038 #endif
1039 }
1040
1041 /* XXX casting to (sy_call_t *) is bogus, as usual. */
1042 static sy_call_t *shmcalls[] = {
1043         (sy_call_t *)sys_shmat, (sy_call_t *)oshmctl,
1044         (sy_call_t *)sys_shmdt, (sy_call_t *)sys_shmget,
1045         (sy_call_t *)freebsd7_shmctl
1046 };
1047
1048 int
1049 sys_shmsys(td, uap)
1050         struct thread *td;
1051         /* XXX actually varargs. */
1052         struct shmsys_args /* {
1053                 int     which;
1054                 int     a2;
1055                 int     a3;
1056                 int     a4;
1057         } */ *uap;
1058 {
1059         int error;
1060
1061         if (!prison_allow(td->td_ucred, PR_ALLOW_SYSVIPC))
1062                 return (ENOSYS);
1063         if (uap->which < 0 ||
1064             uap->which >= sizeof(shmcalls)/sizeof(shmcalls[0]))
1065                 return (EINVAL);
1066         mtx_lock(&Giant);
1067         error = (*shmcalls[uap->which])(td, &uap->a2);
1068         mtx_unlock(&Giant);
1069         return (error);
1070 }
1071
1072 #endif  /* i386 && (COMPAT_FREEBSD4 || COMPAT_43) */
1073
1074 #ifdef COMPAT_FREEBSD32
1075
1076 int
1077 freebsd32_shmsys(struct thread *td, struct freebsd32_shmsys_args *uap)
1078 {
1079
1080 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1081     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1082         switch (uap->which) {
1083         case 0: {       /* shmat */
1084                 struct shmat_args ap;
1085
1086                 ap.shmid = uap->a2;
1087                 ap.shmaddr = PTRIN(uap->a3);
1088                 ap.shmflg = uap->a4;
1089                 return (sysent[SYS_shmat].sy_call(td, &ap));
1090         }
1091         case 2: {       /* shmdt */
1092                 struct shmdt_args ap;
1093
1094                 ap.shmaddr = PTRIN(uap->a2);
1095                 return (sysent[SYS_shmdt].sy_call(td, &ap));
1096         }
1097         case 3: {       /* shmget */
1098                 struct shmget_args ap;
1099
1100                 ap.key = uap->a2;
1101                 ap.size = uap->a3;
1102                 ap.shmflg = uap->a4;
1103                 return (sysent[SYS_shmget].sy_call(td, &ap));
1104         }
1105         case 4: {       /* shmctl */
1106                 struct freebsd7_freebsd32_shmctl_args ap;
1107
1108                 ap.shmid = uap->a2;
1109                 ap.cmd = uap->a3;
1110                 ap.buf = PTRIN(uap->a4);
1111                 return (freebsd7_freebsd32_shmctl(td, &ap));
1112         }
1113         case 1:         /* oshmctl */
1114         default:
1115                 return (EINVAL);
1116         }
1117 #else
1118         return (nosys(td, NULL));
1119 #endif
1120 }
1121
1122 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1123     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1124 int
1125 freebsd7_freebsd32_shmctl(struct thread *td,
1126     struct freebsd7_freebsd32_shmctl_args *uap)
1127 {
1128         int error = 0;
1129         union {
1130                 struct shmid_ds shmid_ds;
1131                 struct shm_info shm_info;
1132                 struct shminfo shminfo;
1133         } u;
1134         union {
1135                 struct shmid_ds32_old shmid_ds32;
1136                 struct shm_info32 shm_info32;
1137                 struct shminfo32 shminfo32;
1138         } u32;
1139         size_t sz;
1140
1141         if (uap->cmd == IPC_SET) {
1142                 if ((error = copyin(uap->buf, &u32.shmid_ds32,
1143                     sizeof(u32.shmid_ds32))))
1144                         goto done;
1145                 freebsd32_ipcperm_old_in(&u32.shmid_ds32.shm_perm,
1146                     &u.shmid_ds.shm_perm);
1147                 CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1148                 CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1149                 CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1150                 CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1151                 CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1152                 CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1153                 CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1154         }
1155
1156         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1157         if (error)
1158                 goto done;
1159
1160         /* Cases in which we need to copyout */
1161         switch (uap->cmd) {
1162         case IPC_INFO:
1163                 CP(u.shminfo, u32.shminfo32, shmmax);
1164                 CP(u.shminfo, u32.shminfo32, shmmin);
1165                 CP(u.shminfo, u32.shminfo32, shmmni);
1166                 CP(u.shminfo, u32.shminfo32, shmseg);
1167                 CP(u.shminfo, u32.shminfo32, shmall);
1168                 error = copyout(&u32.shminfo32, uap->buf,
1169                     sizeof(u32.shminfo32));
1170                 break;
1171         case SHM_INFO:
1172                 CP(u.shm_info, u32.shm_info32, used_ids);
1173                 CP(u.shm_info, u32.shm_info32, shm_rss);
1174                 CP(u.shm_info, u32.shm_info32, shm_tot);
1175                 CP(u.shm_info, u32.shm_info32, shm_swp);
1176                 CP(u.shm_info, u32.shm_info32, swap_attempts);
1177                 CP(u.shm_info, u32.shm_info32, swap_successes);
1178                 error = copyout(&u32.shm_info32, uap->buf,
1179                     sizeof(u32.shm_info32));
1180                 break;
1181         case SHM_STAT:
1182         case IPC_STAT:
1183                 freebsd32_ipcperm_old_out(&u.shmid_ds.shm_perm,
1184                     &u32.shmid_ds32.shm_perm);
1185                 if (u.shmid_ds.shm_segsz > INT32_MAX)
1186                         u32.shmid_ds32.shm_segsz = INT32_MAX;
1187                 else
1188                         CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1189                 CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1190                 CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1191                 CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1192                 CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1193                 CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1194                 CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1195                 u32.shmid_ds32.shm_internal = 0;
1196                 error = copyout(&u32.shmid_ds32, uap->buf,
1197                     sizeof(u32.shmid_ds32));
1198                 break;
1199         }
1200
1201 done:
1202         if (error) {
1203                 /* Invalidate the return value */
1204                 td->td_retval[0] = -1;
1205         }
1206         return (error);
1207 }
1208 #endif
1209
1210 int
1211 freebsd32_shmctl(struct thread *td, struct freebsd32_shmctl_args *uap)
1212 {
1213         int error = 0;
1214         union {
1215                 struct shmid_ds shmid_ds;
1216                 struct shm_info shm_info;
1217                 struct shminfo shminfo;
1218         } u;
1219         union {
1220                 struct shmid_ds32 shmid_ds32;
1221                 struct shm_info32 shm_info32;
1222                 struct shminfo32 shminfo32;
1223         } u32;
1224         size_t sz;
1225
1226         if (uap->cmd == IPC_SET) {
1227                 if ((error = copyin(uap->buf, &u32.shmid_ds32,
1228                     sizeof(u32.shmid_ds32))))
1229                         goto done;
1230                 freebsd32_ipcperm_in(&u32.shmid_ds32.shm_perm,
1231                     &u.shmid_ds.shm_perm);
1232                 CP(u32.shmid_ds32, u.shmid_ds, shm_segsz);
1233                 CP(u32.shmid_ds32, u.shmid_ds, shm_lpid);
1234                 CP(u32.shmid_ds32, u.shmid_ds, shm_cpid);
1235                 CP(u32.shmid_ds32, u.shmid_ds, shm_nattch);
1236                 CP(u32.shmid_ds32, u.shmid_ds, shm_atime);
1237                 CP(u32.shmid_ds32, u.shmid_ds, shm_dtime);
1238                 CP(u32.shmid_ds32, u.shmid_ds, shm_ctime);
1239         }
1240
1241         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&u, &sz);
1242         if (error)
1243                 goto done;
1244
1245         /* Cases in which we need to copyout */
1246         switch (uap->cmd) {
1247         case IPC_INFO:
1248                 CP(u.shminfo, u32.shminfo32, shmmax);
1249                 CP(u.shminfo, u32.shminfo32, shmmin);
1250                 CP(u.shminfo, u32.shminfo32, shmmni);
1251                 CP(u.shminfo, u32.shminfo32, shmseg);
1252                 CP(u.shminfo, u32.shminfo32, shmall);
1253                 error = copyout(&u32.shminfo32, uap->buf,
1254                     sizeof(u32.shminfo32));
1255                 break;
1256         case SHM_INFO:
1257                 CP(u.shm_info, u32.shm_info32, used_ids);
1258                 CP(u.shm_info, u32.shm_info32, shm_rss);
1259                 CP(u.shm_info, u32.shm_info32, shm_tot);
1260                 CP(u.shm_info, u32.shm_info32, shm_swp);
1261                 CP(u.shm_info, u32.shm_info32, swap_attempts);
1262                 CP(u.shm_info, u32.shm_info32, swap_successes);
1263                 error = copyout(&u32.shm_info32, uap->buf,
1264                     sizeof(u32.shm_info32));
1265                 break;
1266         case SHM_STAT:
1267         case IPC_STAT:
1268                 freebsd32_ipcperm_out(&u.shmid_ds.shm_perm,
1269                     &u32.shmid_ds32.shm_perm);
1270                 if (u.shmid_ds.shm_segsz > INT32_MAX)
1271                         u32.shmid_ds32.shm_segsz = INT32_MAX;
1272                 else
1273                         CP(u.shmid_ds, u32.shmid_ds32, shm_segsz);
1274                 CP(u.shmid_ds, u32.shmid_ds32, shm_lpid);
1275                 CP(u.shmid_ds, u32.shmid_ds32, shm_cpid);
1276                 CP(u.shmid_ds, u32.shmid_ds32, shm_nattch);
1277                 CP(u.shmid_ds, u32.shmid_ds32, shm_atime);
1278                 CP(u.shmid_ds, u32.shmid_ds32, shm_dtime);
1279                 CP(u.shmid_ds, u32.shmid_ds32, shm_ctime);
1280                 error = copyout(&u32.shmid_ds32, uap->buf,
1281                     sizeof(u32.shmid_ds32));
1282                 break;
1283         }
1284
1285 done:
1286         if (error) {
1287                 /* Invalidate the return value */
1288                 td->td_retval[0] = -1;
1289         }
1290         return (error);
1291 }
1292 #endif
1293
1294 #if defined(COMPAT_FREEBSD4) || defined(COMPAT_FREEBSD5) || \
1295     defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD7)
1296
1297 #ifndef CP
1298 #define CP(src, dst, fld)       do { (dst).fld = (src).fld; } while (0)
1299 #endif
1300
1301 #ifndef _SYS_SYSPROTO_H_
1302 struct freebsd7_shmctl_args {
1303         int shmid;
1304         int cmd;
1305         struct shmid_ds_old *buf;
1306 };
1307 #endif
1308 int
1309 freebsd7_shmctl(td, uap)
1310         struct thread *td;
1311         struct freebsd7_shmctl_args *uap;
1312 {
1313         int error = 0;
1314         struct shmid_ds_old old;
1315         struct shmid_ds buf;
1316         size_t bufsz;
1317
1318         /*
1319          * The only reason IPC_INFO, SHM_INFO, SHM_STAT exists is to support
1320          * Linux binaries.  If we see the call come through the FreeBSD ABI,
1321          * return an error back to the user since we do not to support this.
1322          */
1323         if (uap->cmd == IPC_INFO || uap->cmd == SHM_INFO ||
1324             uap->cmd == SHM_STAT)
1325                 return (EINVAL);
1326
1327         /* IPC_SET needs to copyin the buffer before calling kern_shmctl */
1328         if (uap->cmd == IPC_SET) {
1329                 if ((error = copyin(uap->buf, &old, sizeof(old))))
1330                         goto done;
1331                 ipcperm_old2new(&old.shm_perm, &buf.shm_perm);
1332                 CP(old, buf, shm_segsz);
1333                 CP(old, buf, shm_lpid);
1334                 CP(old, buf, shm_cpid);
1335                 CP(old, buf, shm_nattch);
1336                 CP(old, buf, shm_atime);
1337                 CP(old, buf, shm_dtime);
1338                 CP(old, buf, shm_ctime);
1339         }
1340
1341         error = kern_shmctl(td, uap->shmid, uap->cmd, (void *)&buf, &bufsz);
1342         if (error)
1343                 goto done;
1344
1345         /* Cases in which we need to copyout */
1346         switch (uap->cmd) {
1347         case IPC_STAT:
1348                 ipcperm_new2old(&buf.shm_perm, &old.shm_perm);
1349                 if (buf.shm_segsz > INT_MAX)
1350                         old.shm_segsz = INT_MAX;
1351                 else
1352                         CP(buf, old, shm_segsz);
1353                 CP(buf, old, shm_lpid);
1354                 CP(buf, old, shm_cpid);
1355                 if (buf.shm_nattch > SHRT_MAX)
1356                         old.shm_nattch = SHRT_MAX;
1357                 else
1358                         CP(buf, old, shm_nattch);
1359                 CP(buf, old, shm_atime);
1360                 CP(buf, old, shm_dtime);
1361                 CP(buf, old, shm_ctime);
1362                 old.shm_internal = NULL;
1363                 error = copyout(&old, uap->buf, sizeof(old));
1364                 break;
1365         }
1366
1367 done:
1368         if (error) {
1369                 /* Invalidate the return value */
1370                 td->td_retval[0] = -1;
1371         }
1372         return (error);
1373 }
1374
1375 #endif  /* COMPAT_FREEBSD4 || COMPAT_FREEBSD5 || COMPAT_FREEBSD6 ||
1376            COMPAT_FREEBSD7 */
1377
1378 static int
1379 sysvshm_modload(struct module *module, int cmd, void *arg)
1380 {
1381         int error = 0;
1382
1383         switch (cmd) {
1384         case MOD_LOAD:
1385                 error = shminit();
1386                 if (error != 0)
1387                         shmunload();
1388                 break;
1389         case MOD_UNLOAD:
1390                 error = shmunload();
1391                 break;
1392         case MOD_SHUTDOWN:
1393                 break;
1394         default:
1395                 error = EINVAL;
1396                 break;
1397         }
1398         return (error);
1399 }
1400
1401 static moduledata_t sysvshm_mod = {
1402         "sysvshm",
1403         &sysvshm_modload,
1404         NULL
1405 };
1406
1407 DECLARE_MODULE(sysvshm, sysvshm_mod, SI_SUB_SYSV_SHM, SI_ORDER_FIRST);
1408 MODULE_VERSION(sysvshm, 1);