Annotation of sys/kern/sysv_shm.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: sysv_shm.c,v 1.47 2007/05/29 10:44:28 sturm Exp $ */
! 2: /* $NetBSD: sysv_shm.c,v 1.50 1998/10/21 22:24:29 tron Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 2002 Todd C. Miller <Todd.Miller@courtesan.com>
! 6: *
! 7: * Permission to use, copy, modify, and distribute this software for any
! 8: * purpose with or without fee is hereby granted, provided that the above
! 9: * copyright notice and this permission notice appear in all copies.
! 10: *
! 11: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
! 12: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
! 13: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
! 14: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
! 15: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
! 16: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
! 17: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
! 18: *
! 19: * Sponsored in part by the Defense Advanced Research Projects
! 20: * Agency (DARPA) and Air Force Research Laboratory, Air Force
! 21: * Materiel Command, USAF, under agreement number F39502-99-1-0512.
! 22: */
! 23: /*
! 24: * Copyright (c) 1994 Adam Glass and Charles M. Hannum. All rights reserved.
! 25: *
! 26: * Redistribution and use in source and binary forms, with or without
! 27: * modification, are permitted provided that the following conditions
! 28: * are met:
! 29: * 1. Redistributions of source code must retain the above copyright
! 30: * notice, this list of conditions and the following disclaimer.
! 31: * 2. Redistributions in binary form must reproduce the above copyright
! 32: * notice, this list of conditions and the following disclaimer in the
! 33: * documentation and/or other materials provided with the distribution.
! 34: * 3. All advertising materials mentioning features or use of this software
! 35: * must display the following acknowledgement:
! 36: * This product includes software developed by Adam Glass and Charles M.
! 37: * Hannum.
! 38: * 4. The names of the authors may not be used to endorse or promote products
! 39: * derived from this software without specific prior written permission.
! 40: *
! 41: * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
! 42: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
! 43: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
! 44: * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
! 45: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
! 46: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
! 47: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
! 48: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
! 49: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
! 50: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
! 51: */
! 52:
! 53: #include <sys/param.h>
! 54: #include <sys/kernel.h>
! 55: #include <sys/shm.h>
! 56: #include <sys/proc.h>
! 57: #include <sys/uio.h>
! 58: #include <sys/time.h>
! 59: #include <sys/malloc.h>
! 60: #include <sys/mman.h>
! 61: #include <sys/pool.h>
! 62: #include <sys/systm.h>
! 63: #include <sys/sysctl.h>
! 64: #include <sys/stat.h>
! 65:
! 66: #include <sys/mount.h>
! 67: #include <sys/syscallargs.h>
! 68:
! 69: #include <uvm/uvm_extern.h>
! 70:
! 71: extern struct shminfo shminfo;
! 72: struct shmid_ds **shmsegs; /* linear mapping of shmid -> shmseg */
! 73: struct pool shm_pool;
! 74: unsigned short *shmseqs; /* array of shm sequence numbers */
! 75:
! 76: struct shmid_ds *shm_find_segment_by_shmid(int);
! 77:
! 78: /*
! 79: * Provides the following externally accessible functions:
! 80: *
! 81: * shminit(void); initialization
! 82: * shmexit(struct vmspace *) cleanup
! 83: * shmfork(struct vmspace *, struct vmspace *) fork handling
! 84: * shmsys(arg1, arg2, arg3, arg4); shm{at,ctl,dt,get}(arg2, arg3, arg4)
! 85: *
! 86: * Structures:
! 87: * shmsegs (an array of 'struct shmid_ds *')
! 88: * per proc 'struct shmmap_head' with an array of 'struct shmmap_state'
! 89: */
! 90:
! 91: #define SHMSEG_REMOVED 0x0200 /* can't overlap ACCESSPERMS */
! 92: #define SHMSEG_RMLINGER 0x0400
! 93:
! 94: int shm_last_free, shm_nused, shm_committed;
! 95:
! 96: struct shm_handle {
! 97: struct uvm_object *shm_object;
! 98: };
! 99:
! 100: struct shmmap_state {
! 101: vaddr_t va;
! 102: int shmid;
! 103: };
! 104:
! 105: struct shmmap_head {
! 106: int shmseg;
! 107: struct shmmap_state state[1];
! 108: };
! 109:
! 110: int shm_find_segment_by_key(key_t);
! 111: void shm_deallocate_segment(struct shmid_ds *);
! 112: int shm_delete_mapping(struct vmspace *, struct shmmap_state *);
! 113: int shmget_existing(struct proc *, struct sys_shmget_args *,
! 114: int, int, register_t *);
! 115: int shmget_allocate_segment(struct proc *, struct sys_shmget_args *,
! 116: int, register_t *);
! 117:
! 118: int
! 119: shm_find_segment_by_key(key_t key)
! 120: {
! 121: struct shmid_ds *shmseg;
! 122: int i;
! 123:
! 124: for (i = 0; i < shminfo.shmmni; i++) {
! 125: shmseg = shmsegs[i];
! 126: if (shmseg != NULL && shmseg->shm_perm.key == key)
! 127: return (i);
! 128: }
! 129: return (-1);
! 130: }
! 131:
! 132: struct shmid_ds *
! 133: shm_find_segment_by_shmid(int shmid)
! 134: {
! 135: int segnum;
! 136: struct shmid_ds *shmseg;
! 137:
! 138: segnum = IPCID_TO_IX(shmid);
! 139: if (segnum < 0 || segnum >= shminfo.shmmni ||
! 140: (shmseg = shmsegs[segnum]) == NULL ||
! 141: shmseg->shm_perm.seq != IPCID_TO_SEQ(shmid))
! 142: return (NULL);
! 143: if ((shmseg->shm_perm.mode & (SHMSEG_REMOVED|SHMSEG_RMLINGER)) == SHMSEG_REMOVED)
! 144: return (NULL);
! 145: return (shmseg);
! 146: }
! 147:
! 148: void
! 149: shm_deallocate_segment(struct shmid_ds *shmseg)
! 150: {
! 151: struct shm_handle *shm_handle;
! 152: size_t size;
! 153:
! 154: shm_handle = shmseg->shm_internal;
! 155: size = round_page(shmseg->shm_segsz);
! 156: uao_detach(shm_handle->shm_object);
! 157: pool_put(&shm_pool, shmseg);
! 158: shm_committed -= btoc(size);
! 159: shm_nused--;
! 160: }
! 161:
! 162: int
! 163: shm_delete_mapping(struct vmspace *vm, struct shmmap_state *shmmap_s)
! 164: {
! 165: struct shmid_ds *shmseg;
! 166: int segnum;
! 167: size_t size;
! 168:
! 169: segnum = IPCID_TO_IX(shmmap_s->shmid);
! 170: if (segnum < 0 || segnum >= shminfo.shmmni ||
! 171: (shmseg = shmsegs[segnum]) == NULL)
! 172: return (EINVAL);
! 173: size = round_page(shmseg->shm_segsz);
! 174: uvm_deallocate(&vm->vm_map, shmmap_s->va, size);
! 175: shmmap_s->shmid = -1;
! 176: shmseg->shm_dtime = time_second;
! 177: if ((--shmseg->shm_nattch <= 0) &&
! 178: (shmseg->shm_perm.mode & SHMSEG_REMOVED)) {
! 179: shm_deallocate_segment(shmseg);
! 180: shm_last_free = segnum;
! 181: shmsegs[shm_last_free] = NULL;
! 182: }
! 183: return (0);
! 184: }
! 185:
! 186: int
! 187: sys_shmdt(struct proc *p, void *v, register_t *retval)
! 188: {
! 189: struct sys_shmdt_args /* {
! 190: syscallarg(const void *) shmaddr;
! 191: } */ *uap = v;
! 192: struct shmmap_head *shmmap_h;
! 193: struct shmmap_state *shmmap_s;
! 194: int i;
! 195:
! 196: shmmap_h = (struct shmmap_head *)p->p_vmspace->vm_shm;
! 197: if (shmmap_h == NULL)
! 198: return (EINVAL);
! 199:
! 200: for (i = 0, shmmap_s = shmmap_h->state; i < shmmap_h->shmseg;
! 201: i++, shmmap_s++)
! 202: if (shmmap_s->shmid != -1 &&
! 203: shmmap_s->va == (vaddr_t)SCARG(uap, shmaddr))
! 204: break;
! 205: if (i == shmmap_h->shmseg)
! 206: return (EINVAL);
! 207: return (shm_delete_mapping(p->p_vmspace, shmmap_s));
! 208: }
! 209:
! 210: int
! 211: sys_shmat(struct proc *p, void *v, register_t *retval)
! 212: {
! 213: struct sys_shmat_args /* {
! 214: syscallarg(int) shmid;
! 215: syscallarg(const void *) shmaddr;
! 216: syscallarg(int) shmflg;
! 217: } */ *uap = v;
! 218: int error, i, flags;
! 219: struct ucred *cred = p->p_ucred;
! 220: struct shmid_ds *shmseg;
! 221: struct shmmap_head *shmmap_h;
! 222: struct shmmap_state *shmmap_s;
! 223: struct shm_handle *shm_handle;
! 224: vaddr_t attach_va;
! 225: vm_prot_t prot;
! 226: vsize_t size;
! 227:
! 228: shmmap_h = (struct shmmap_head *)p->p_vmspace->vm_shm;
! 229: if (shmmap_h == NULL) {
! 230: size = sizeof(int) +
! 231: shminfo.shmseg * sizeof(struct shmmap_state);
! 232: shmmap_h = malloc(size, M_SHM, M_WAITOK);
! 233: shmmap_h->shmseg = shminfo.shmseg;
! 234: for (i = 0, shmmap_s = shmmap_h->state; i < shmmap_h->shmseg;
! 235: i++, shmmap_s++)
! 236: shmmap_s->shmid = -1;
! 237: p->p_vmspace->vm_shm = (caddr_t)shmmap_h;
! 238: }
! 239: shmseg = shm_find_segment_by_shmid(SCARG(uap, shmid));
! 240: if (shmseg == NULL)
! 241: return (EINVAL);
! 242: error = ipcperm(cred, &shmseg->shm_perm,
! 243: (SCARG(uap, shmflg) & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
! 244: if (error)
! 245: return (error);
! 246: for (i = 0, shmmap_s = shmmap_h->state; i < shmmap_h->shmseg; i++) {
! 247: if (shmmap_s->shmid == -1)
! 248: break;
! 249: shmmap_s++;
! 250: }
! 251: if (i >= shmmap_h->shmseg)
! 252: return (EMFILE);
! 253: size = round_page(shmseg->shm_segsz);
! 254: prot = VM_PROT_READ;
! 255: if ((SCARG(uap, shmflg) & SHM_RDONLY) == 0)
! 256: prot |= VM_PROT_WRITE;
! 257: flags = MAP_ANON | MAP_SHARED;
! 258: if (SCARG(uap, shmaddr)) {
! 259: flags |= MAP_FIXED;
! 260: if (SCARG(uap, shmflg) & SHM_RND)
! 261: attach_va =
! 262: (vaddr_t)SCARG(uap, shmaddr) & ~(SHMLBA-1);
! 263: else if (((vaddr_t)SCARG(uap, shmaddr) & (SHMLBA-1)) == 0)
! 264: attach_va = (vaddr_t)SCARG(uap, shmaddr);
! 265: else
! 266: return (EINVAL);
! 267: } else {
! 268: /* This is just a hint to uvm_map() about where to put it. */
! 269: attach_va = uvm_map_hint(p, prot);
! 270: }
! 271: shm_handle = shmseg->shm_internal;
! 272: uao_reference(shm_handle->shm_object);
! 273: error = uvm_map(&p->p_vmspace->vm_map, &attach_va, size,
! 274: shm_handle->shm_object, 0, 0, UVM_MAPFLAG(prot, prot,
! 275: UVM_INH_SHARE, UVM_ADV_RANDOM, 0));
! 276: if (error) {
! 277: uao_detach(shm_handle->shm_object);
! 278: return (error);
! 279: }
! 280:
! 281: shmmap_s->va = attach_va;
! 282: shmmap_s->shmid = SCARG(uap, shmid);
! 283: shmseg->shm_lpid = p->p_pid;
! 284: shmseg->shm_atime = time_second;
! 285: shmseg->shm_nattch++;
! 286: *retval = attach_va;
! 287: return (0);
! 288: }
! 289:
! 290: int
! 291: sys_shmctl(struct proc *p, void *v, register_t *retval)
! 292: {
! 293: struct sys_shmctl_args /* {
! 294: syscallarg(int) shmid;
! 295: syscallarg(int) cmd;
! 296: syscallarg(struct shmid_ds *) buf;
! 297: } */ *uap = v;
! 298:
! 299: return (shmctl1(p, SCARG(uap, shmid), SCARG(uap, cmd),
! 300: (caddr_t)SCARG(uap, buf), copyin, copyout));
! 301: }
! 302:
! 303: int
! 304: shmctl1(struct proc *p, int shmid, int cmd, caddr_t buf,
! 305: int (*ds_copyin)(const void *, void *, size_t),
! 306: int (*ds_copyout)(const void *, void *, size_t))
! 307: {
! 308: struct ucred *cred = p->p_ucred;
! 309: struct shmid_ds inbuf, *shmseg;
! 310: int error;
! 311:
! 312: shmseg = shm_find_segment_by_shmid(shmid);
! 313: if (shmseg == NULL)
! 314: return (EINVAL);
! 315: switch (cmd) {
! 316: case IPC_STAT:
! 317: if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_R)) != 0)
! 318: return (error);
! 319: error = ds_copyout(shmseg, buf, sizeof(inbuf));
! 320: if (error)
! 321: return (error);
! 322: break;
! 323: case IPC_SET:
! 324: if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
! 325: return (error);
! 326: error = ds_copyin(buf, &inbuf, sizeof(inbuf));
! 327: if (error)
! 328: return (error);
! 329: shmseg->shm_perm.uid = inbuf.shm_perm.uid;
! 330: shmseg->shm_perm.gid = inbuf.shm_perm.gid;
! 331: shmseg->shm_perm.mode =
! 332: (shmseg->shm_perm.mode & ~ACCESSPERMS) |
! 333: (inbuf.shm_perm.mode & ACCESSPERMS);
! 334: shmseg->shm_ctime = time_second;
! 335: break;
! 336: case IPC_RMID:
! 337: if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
! 338: return (error);
! 339: shmseg->shm_perm.key = IPC_PRIVATE;
! 340: shmseg->shm_perm.mode |= SHMSEG_REMOVED;
! 341: if (shmseg->shm_nattch <= 0) {
! 342: shm_deallocate_segment(shmseg);
! 343: shm_last_free = IPCID_TO_IX(shmid);
! 344: shmsegs[shm_last_free] = NULL;
! 345: }
! 346: break;
! 347: case SHM_LOCK:
! 348: case SHM_UNLOCK:
! 349: default:
! 350: return (EINVAL);
! 351: }
! 352: return (0);
! 353: }
! 354:
! 355: int
! 356: shmget_existing(struct proc *p,
! 357: struct sys_shmget_args /* {
! 358: syscallarg(key_t) key;
! 359: syscallarg(size_t) size;
! 360: syscallarg(int) shmflg;
! 361: } */ *uap,
! 362: int mode, int segnum, register_t *retval)
! 363: {
! 364: struct shmid_ds *shmseg;
! 365: struct ucred *cred = p->p_ucred;
! 366: int error;
! 367:
! 368: shmseg = shmsegs[segnum]; /* We assume the segnum is valid */
! 369: if ((error = ipcperm(cred, &shmseg->shm_perm, mode)) != 0)
! 370: return (error);
! 371: if (SCARG(uap, size) && SCARG(uap, size) > shmseg->shm_segsz)
! 372: return (EINVAL);
! 373: if ((SCARG(uap, shmflg) & (IPC_CREAT | IPC_EXCL)) ==
! 374: (IPC_CREAT | IPC_EXCL))
! 375: return (EEXIST);
! 376: *retval = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
! 377: return (0);
! 378: }
! 379:
! 380: int
! 381: shmget_allocate_segment(struct proc *p,
! 382: struct sys_shmget_args /* {
! 383: syscallarg(key_t) key;
! 384: syscallarg(size_t) size;
! 385: syscallarg(int) shmflg;
! 386: } */ *uap,
! 387: int mode, register_t *retval)
! 388: {
! 389: size_t size;
! 390: key_t key;
! 391: int segnum;
! 392: struct ucred *cred = p->p_ucred;
! 393: struct shmid_ds *shmseg;
! 394: struct shm_handle *shm_handle;
! 395: int error = 0;
! 396:
! 397: if (SCARG(uap, size) < shminfo.shmmin ||
! 398: SCARG(uap, size) > shminfo.shmmax)
! 399: return (EINVAL);
! 400: if (shm_nused >= shminfo.shmmni) /* any shmids left? */
! 401: return (ENOSPC);
! 402: size = round_page(SCARG(uap, size));
! 403: if (shm_committed + btoc(size) > shminfo.shmall)
! 404: return (ENOMEM);
! 405: shm_nused++;
! 406: shm_committed += btoc(size);
! 407:
! 408: /*
! 409: * If a key has been specified and we had to wait for memory
! 410: * to be freed up we need to verify that no one has allocated
! 411: * the key we want in the meantime. Yes, this is ugly.
! 412: */
! 413: key = SCARG(uap, key);
! 414: shmseg = pool_get(&shm_pool, key == IPC_PRIVATE ? PR_WAITOK : 0);
! 415: if (shmseg == NULL) {
! 416: shmseg = pool_get(&shm_pool, PR_WAITOK);
! 417: if (shm_find_segment_by_key(key) != -1) {
! 418: pool_put(&shm_pool, shmseg);
! 419: shm_nused--;
! 420: shm_committed -= btoc(size);
! 421: return (EAGAIN);
! 422: }
! 423: }
! 424:
! 425: /* XXX - hash shmids instead */
! 426: if (shm_last_free < 0) {
! 427: for (segnum = 0; segnum < shminfo.shmmni && shmsegs[segnum];
! 428: segnum++)
! 429: ;
! 430: if (segnum == shminfo.shmmni)
! 431: panic("shmseg free count inconsistent");
! 432: } else {
! 433: segnum = shm_last_free;
! 434: if (++shm_last_free >= shminfo.shmmni || shmsegs[shm_last_free])
! 435: shm_last_free = -1;
! 436: }
! 437: shmsegs[segnum] = shmseg;
! 438:
! 439: shm_handle = (struct shm_handle *)((caddr_t)shmseg + sizeof(*shmseg));
! 440: shm_handle->shm_object = uao_create(size, 0);
! 441:
! 442: shmseg->shm_perm.cuid = shmseg->shm_perm.uid = cred->cr_uid;
! 443: shmseg->shm_perm.cgid = shmseg->shm_perm.gid = cred->cr_gid;
! 444: shmseg->shm_perm.mode = (mode & (ACCESSPERMS|SHMSEG_RMLINGER));
! 445: shmseg->shm_perm.seq = shmseqs[segnum] = (shmseqs[segnum] + 1) & 0x7fff;
! 446: shmseg->shm_perm.key = key;
! 447: shmseg->shm_segsz = SCARG(uap, size);
! 448: shmseg->shm_cpid = p->p_pid;
! 449: shmseg->shm_lpid = shmseg->shm_nattch = 0;
! 450: shmseg->shm_atime = shmseg->shm_dtime = 0;
! 451: shmseg->shm_ctime = time_second;
! 452: shmseg->shm_internal = shm_handle;
! 453:
! 454: *retval = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
! 455: return (error);
! 456: }
! 457:
! 458: int
! 459: sys_shmget(struct proc *p, void *v, register_t *retval)
! 460: {
! 461: struct sys_shmget_args /* {
! 462: syscallarg(key_t) key;
! 463: syscallarg(size_t) size;
! 464: syscallarg(int) shmflg;
! 465: } */ *uap = v;
! 466: int segnum, mode, error;
! 467:
! 468: mode = SCARG(uap, shmflg) & ACCESSPERMS;
! 469: if (SCARG(uap, shmflg) & _SHM_RMLINGER)
! 470: mode |= SHMSEG_RMLINGER;
! 471:
! 472: if (SCARG(uap, key) != IPC_PRIVATE) {
! 473: again:
! 474: segnum = shm_find_segment_by_key(SCARG(uap, key));
! 475: if (segnum >= 0)
! 476: return (shmget_existing(p, uap, mode, segnum, retval));
! 477: if ((SCARG(uap, shmflg) & IPC_CREAT) == 0)
! 478: return (ENOENT);
! 479: }
! 480: error = shmget_allocate_segment(p, uap, mode, retval);
! 481: if (error == EAGAIN)
! 482: goto again;
! 483: return (error);
! 484: }
! 485:
! 486: void
! 487: shmfork(struct vmspace *vm1, struct vmspace *vm2)
! 488: {
! 489: struct shmmap_head *shmmap_h;
! 490: struct shmmap_state *shmmap_s;
! 491: struct shmid_ds *shmseg;
! 492: size_t size;
! 493: int i;
! 494:
! 495: if (vm1->vm_shm == NULL) {
! 496: vm2->vm_shm = NULL;
! 497: return;
! 498: }
! 499:
! 500: shmmap_h = (struct shmmap_head *)vm1->vm_shm;
! 501: size = sizeof(int) + shmmap_h->shmseg * sizeof(struct shmmap_state);
! 502: vm2->vm_shm = malloc(size, M_SHM, M_WAITOK);
! 503: bcopy(vm1->vm_shm, vm2->vm_shm, size);
! 504: for (i = 0, shmmap_s = shmmap_h->state; i < shmmap_h->shmseg;
! 505: i++, shmmap_s++) {
! 506: if (shmmap_s->shmid != -1 &&
! 507: (shmseg = shmsegs[IPCID_TO_IX(shmmap_s->shmid)]) != NULL)
! 508: shmseg->shm_nattch++;
! 509: }
! 510: }
! 511:
! 512: void
! 513: shmexit(struct vmspace *vm)
! 514: {
! 515: struct shmmap_head *shmmap_h;
! 516: struct shmmap_state *shmmap_s;
! 517: int i;
! 518:
! 519: shmmap_h = (struct shmmap_head *)vm->vm_shm;
! 520: if (shmmap_h == NULL)
! 521: return;
! 522: for (i = 0, shmmap_s = shmmap_h->state; i < shmmap_h->shmseg;
! 523: i++, shmmap_s++)
! 524: if (shmmap_s->shmid != -1)
! 525: shm_delete_mapping(vm, shmmap_s);
! 526: free(vm->vm_shm, M_SHM);
! 527: vm->vm_shm = NULL;
! 528: }
! 529:
! 530: void
! 531: shminit(void)
! 532: {
! 533:
! 534: pool_init(&shm_pool, sizeof(struct shmid_ds) +
! 535: sizeof(struct shm_handle), 0, 0, 0, "shmpl",
! 536: &pool_allocator_nointr);
! 537: shmsegs = malloc(shminfo.shmmni * sizeof(struct shmid_ds *),
! 538: M_SHM, M_WAITOK);
! 539: bzero(shmsegs, shminfo.shmmni * sizeof(struct shmid_ds *));
! 540: shmseqs = malloc(shminfo.shmmni * sizeof(unsigned short),
! 541: M_SHM, M_WAITOK);
! 542: bzero(shmseqs, shminfo.shmmni * sizeof(unsigned short));
! 543:
! 544: shminfo.shmmax *= PAGE_SIZE; /* actually in pages */
! 545: shm_last_free = 0;
! 546: shm_nused = 0;
! 547: shm_committed = 0;
! 548: }
! 549:
! 550: /*
! 551: * Userland access to struct shminfo.
! 552: */
! 553: int
! 554: sysctl_sysvshm(int *name, u_int namelen, void *oldp, size_t *oldlenp,
! 555: void *newp, size_t newlen)
! 556: {
! 557: int error, val;
! 558: struct shmid_ds **newsegs;
! 559: unsigned short *newseqs;
! 560:
! 561: if (namelen != 2) {
! 562: switch (name[0]) {
! 563: case KERN_SHMINFO_SHMMAX:
! 564: case KERN_SHMINFO_SHMMIN:
! 565: case KERN_SHMINFO_SHMMNI:
! 566: case KERN_SHMINFO_SHMSEG:
! 567: case KERN_SHMINFO_SHMALL:
! 568: break;
! 569: default:
! 570: return (ENOTDIR); /* overloaded */
! 571: }
! 572: }
! 573:
! 574: switch (name[0]) {
! 575: case KERN_SHMINFO_SHMMAX:
! 576: if ((error = sysctl_int(oldp, oldlenp, newp, newlen,
! 577: &shminfo.shmmax)) || newp == NULL)
! 578: return (error);
! 579:
! 580: /* If new shmmax > shmall, crank shmall */
! 581: if (btoc(round_page(shminfo.shmmax)) > shminfo.shmall)
! 582: shminfo.shmall = btoc(round_page(shminfo.shmmax));
! 583: return (0);
! 584: case KERN_SHMINFO_SHMMIN:
! 585: val = shminfo.shmmin;
! 586: if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &val)) ||
! 587: val == shminfo.shmmin)
! 588: return (error);
! 589: if (val <= 0)
! 590: return (EINVAL); /* shmmin must be >= 1 */
! 591: shminfo.shmmin = val;
! 592: return (0);
! 593: case KERN_SHMINFO_SHMMNI:
! 594: val = shminfo.shmmni;
! 595: if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &val)) ||
! 596: val == shminfo.shmmni)
! 597: return (error);
! 598:
! 599: if (val < shminfo.shmmni || val > 0xffff)
! 600: return (EINVAL);
! 601:
! 602: /* Expand shmsegs and shmseqs arrays */
! 603: newsegs = malloc(val * sizeof(struct shmid_ds *),
! 604: M_SHM, M_WAITOK);
! 605: bcopy(shmsegs, newsegs,
! 606: shminfo.shmmni * sizeof(struct shmid_ds *));
! 607: bzero(newsegs + shminfo.shmmni,
! 608: (val - shminfo.shmmni) * sizeof(struct shmid_ds *));
! 609: free(shmsegs, M_SHM);
! 610: shmsegs = newsegs;
! 611: newseqs = malloc(val * sizeof(unsigned short), M_SHM, M_WAITOK);
! 612: bcopy(shmseqs, newseqs,
! 613: shminfo.shmmni * sizeof(unsigned short));
! 614: bzero(newseqs + shminfo.shmmni,
! 615: (val - shminfo.shmmni) * sizeof(unsigned short));
! 616: free(shmseqs, M_SHM);
! 617: shmseqs = newseqs;
! 618: shminfo.shmmni = val;
! 619: return (0);
! 620: case KERN_SHMINFO_SHMSEG:
! 621: val = shminfo.shmseg;
! 622: if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &val)) ||
! 623: val == shminfo.shmseg)
! 624: return (error);
! 625: if (val <= 0)
! 626: return (EINVAL); /* shmseg must be >= 1 */
! 627: shminfo.shmseg = val;
! 628: return (0);
! 629: case KERN_SHMINFO_SHMALL:
! 630: val = shminfo.shmall;
! 631: if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &val)) ||
! 632: val == shminfo.shmall)
! 633: return (error);
! 634: if (val < shminfo.shmall)
! 635: return (EINVAL); /* can't decrease shmall */
! 636: shminfo.shmall = val;
! 637: return (0);
! 638: default:
! 639: return (EOPNOTSUPP);
! 640: }
! 641: /* NOTREACHED */
! 642: }
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