707 lines
19 KiB
C
707 lines
19 KiB
C
/* $NetBSD: sysv_shm.c,v 1.70 2003/09/10 17:01:04 drochner Exp $ */
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/*-
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* Copyright (c) 1999 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
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* NASA Ames Research Center.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the NetBSD
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* Foundation, Inc. and its contributors.
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* 4. Neither the name of The NetBSD Foundation nor the names of its
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* contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Copyright (c) 1994 Adam Glass and Charles M. Hannum. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by Adam Glass and Charles M.
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* Hannum.
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* 4. The names of the authors may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__KERNEL_RCSID(0, "$NetBSD: sysv_shm.c,v 1.70 2003/09/10 17:01:04 drochner Exp $");
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#define SYSVSHM
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#include <sys/param.h>
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#include <sys/kernel.h>
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#include <sys/shm.h>
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#include <sys/malloc.h>
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#include <sys/mman.h>
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#include <sys/stat.h>
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#include <sys/sysctl.h>
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#include <sys/mount.h> /* XXX for <sys/syscallargs.h> */
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#include <sys/sa.h>
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#include <sys/syscallargs.h>
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#include <sys/queue.h>
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#include <sys/pool.h>
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#include <uvm/uvm_extern.h>
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struct shmid_ds *shm_find_segment_by_shmid __P((int, int));
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MALLOC_DEFINE(M_SHM, "shm", "SVID compatible shared memory segments");
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/*
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* Provides the following externally accessible functions:
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*
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* shminit(void); initialization
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* shmexit(struct vmspace *) cleanup
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* shmfork(struct vmspace *, struct vmspace *) fork handling
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*
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* Structures:
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* shmsegs (an array of 'struct shmid_ds')
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* per proc array of 'struct shmmap_state'
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*/
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#define SHMSEG_FREE 0x0200
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#define SHMSEG_REMOVED 0x0400
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#define SHMSEG_ALLOCATED 0x0800
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#define SHMSEG_WANTED 0x1000
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int shm_last_free, shm_nused, shm_committed;
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struct shmid_ds *shmsegs;
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struct shm_handle {
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struct uvm_object *shm_object;
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};
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struct shmmap_entry {
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SLIST_ENTRY(shmmap_entry) next;
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vaddr_t va;
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int shmid;
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};
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struct pool shmmap_entry_pool;
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struct shmmap_state {
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unsigned int nitems;
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unsigned int nrefs;
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SLIST_HEAD(, shmmap_entry) entries;
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};
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static int shm_find_segment_by_key __P((key_t));
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static void shm_deallocate_segment __P((struct shmid_ds *));
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static void shm_delete_mapping __P((struct vmspace *, struct shmmap_state *,
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struct shmmap_entry *));
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static int shmget_existing __P((struct proc *, struct sys_shmget_args *,
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int, int, register_t *));
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static int shmget_allocate_segment __P((struct proc *, struct sys_shmget_args *,
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int, register_t *));
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static struct shmmap_state *shmmap_getprivate __P((struct proc *));
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static struct shmmap_entry *
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shm_find_mapping __P((struct shmmap_state *, vaddr_t));
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static int
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shm_find_segment_by_key(key)
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key_t key;
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{
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int i;
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for (i = 0; i < shminfo.shmmni; i++)
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if ((shmsegs[i].shm_perm.mode & SHMSEG_ALLOCATED) &&
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shmsegs[i].shm_perm._key == key)
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return i;
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return -1;
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}
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struct shmid_ds *
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shm_find_segment_by_shmid(shmid, findremoved)
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int shmid;
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int findremoved;
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{
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int segnum;
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struct shmid_ds *shmseg;
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segnum = IPCID_TO_IX(shmid);
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if (segnum < 0 || segnum >= shminfo.shmmni)
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return NULL;
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shmseg = &shmsegs[segnum];
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if ((shmseg->shm_perm.mode & SHMSEG_ALLOCATED) == 0)
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return NULL;
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if (!findremoved && ((shmseg->shm_perm.mode & SHMSEG_REMOVED) != 0))
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return NULL;
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if (shmseg->shm_perm._seq != IPCID_TO_SEQ(shmid))
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return NULL;
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return shmseg;
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}
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static void
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shm_deallocate_segment(shmseg)
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struct shmid_ds *shmseg;
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{
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struct shm_handle *shm_handle;
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size_t size;
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shm_handle = shmseg->_shm_internal;
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size = (shmseg->shm_segsz + PGOFSET) & ~PGOFSET;
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uao_detach(shm_handle->shm_object);
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free((caddr_t)shm_handle, M_SHM);
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shmseg->_shm_internal = NULL;
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shm_committed -= btoc(size);
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shmseg->shm_perm.mode = SHMSEG_FREE;
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shm_nused--;
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}
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static void
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shm_delete_mapping(vm, shmmap_s, shmmap_se)
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struct vmspace *vm;
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struct shmmap_state *shmmap_s;
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struct shmmap_entry *shmmap_se;
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{
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struct shmid_ds *shmseg;
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int segnum;
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size_t size;
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segnum = IPCID_TO_IX(shmmap_se->shmid);
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shmseg = &shmsegs[segnum];
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size = (shmseg->shm_segsz + PGOFSET) & ~PGOFSET;
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uvm_deallocate(&vm->vm_map, shmmap_se->va, size);
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SLIST_REMOVE(&shmmap_s->entries, shmmap_se, shmmap_entry, next);
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shmmap_s->nitems--;
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pool_put(&shmmap_entry_pool, shmmap_se);
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shmseg->shm_dtime = time.tv_sec;
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if ((--shmseg->shm_nattch <= 0) &&
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(shmseg->shm_perm.mode & SHMSEG_REMOVED)) {
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shm_deallocate_segment(shmseg);
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shm_last_free = segnum;
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}
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}
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/*
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* Get a non-shared shm map for that vmspace.
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* 3 cases:
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* - no shm map present: create a fresh one
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* - a shm map with refcount=1, just used by ourselves: fine
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* - a shared shm map: copy to a fresh one and adjust refcounts
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*/
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static struct shmmap_state *
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shmmap_getprivate(struct proc *p)
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{
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struct shmmap_state *oshmmap_s, *shmmap_s;
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struct shmmap_entry *oshmmap_se, *shmmap_se;
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oshmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
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if (oshmmap_s && oshmmap_s->nrefs == 1)
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return (oshmmap_s);
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shmmap_s = malloc(sizeof(struct shmmap_state), M_SHM, M_WAITOK);
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memset(shmmap_s, 0, sizeof(struct shmmap_state));
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shmmap_s->nrefs = 1;
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SLIST_INIT(&shmmap_s->entries);
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p->p_vmspace->vm_shm = (caddr_t)shmmap_s;
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if (!oshmmap_s)
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return (shmmap_s);
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#ifdef SHMDEBUG
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printf("shmmap_getprivate: vm %p split (%d entries), was used by %d\n",
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p->p_vmspace, oshmmap_s->nitems, oshmmap_s->nrefs);
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#endif
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SLIST_FOREACH(oshmmap_se, &oshmmap_s->entries, next) {
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shmmap_se = pool_get(&shmmap_entry_pool, PR_WAITOK);
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shmmap_se->va = oshmmap_se->va;
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shmmap_se->shmid = oshmmap_se->shmid;
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SLIST_INSERT_HEAD(&shmmap_s->entries, shmmap_se, next);
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}
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shmmap_s->nitems = oshmmap_s->nitems;
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oshmmap_s->nrefs--;
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return (shmmap_s);
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}
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static struct shmmap_entry *
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shm_find_mapping(map, va)
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struct shmmap_state *map;
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vaddr_t va;
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{
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struct shmmap_entry *shmmap_se;
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SLIST_FOREACH(shmmap_se, &map->entries, next) {
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if (shmmap_se->va == va)
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return shmmap_se;
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}
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return 0;
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}
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int
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sys_shmdt(l, v, retval)
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struct lwp *l;
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void *v;
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register_t *retval;
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{
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struct sys_shmdt_args /* {
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syscallarg(const void *) shmaddr;
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} */ *uap = v;
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struct proc *p = l->l_proc;
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struct shmmap_state *shmmap_s, *shmmap_s1;
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struct shmmap_entry *shmmap_se;
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shmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
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if (shmmap_s == NULL)
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return EINVAL;
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shmmap_se = shm_find_mapping(shmmap_s, (vaddr_t)SCARG(uap, shmaddr));
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if (!shmmap_se)
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return EINVAL;
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shmmap_s1 = shmmap_getprivate(p);
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if (shmmap_s1 != shmmap_s) {
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/* map has been copied, lookup entry in new map */
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shmmap_se = shm_find_mapping(shmmap_s1,
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(vaddr_t)SCARG(uap, shmaddr));
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KASSERT(shmmap_se != NULL);
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}
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#ifdef SHMDEBUG
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printf("shmdt: vm %p: remove %d @%lx\n",
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p->p_vmspace, shmmap_se->shmid, shmmap_se->va);
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#endif
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shm_delete_mapping(p->p_vmspace, shmmap_s1, shmmap_se);
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return 0;
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}
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int
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sys_shmat(l, v, retval)
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struct lwp *l;
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void *v;
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register_t *retval;
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{
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struct sys_shmat_args /* {
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syscallarg(int) shmid;
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syscallarg(const void *) shmaddr;
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syscallarg(int) shmflg;
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} */ *uap = v;
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struct proc *p = l->l_proc;
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vaddr_t attach_va;
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int error;
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error = shmat1(p, SCARG(uap, shmid), SCARG(uap, shmaddr),
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SCARG(uap, shmflg), &attach_va, 0);
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if (error != 0)
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return error;
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retval[0] = attach_va;
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return 0;
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}
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int
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shmat1(p, shmid, shmaddr, shmflg, attachp, findremoved)
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struct proc *p;
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int shmid;
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const void *shmaddr;
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int shmflg;
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vaddr_t *attachp;
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int findremoved;
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{
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int error, flags;
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struct ucred *cred = p->p_ucred;
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struct shmid_ds *shmseg;
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struct shmmap_state *shmmap_s;
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struct shm_handle *shm_handle;
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vaddr_t attach_va;
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vm_prot_t prot;
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vsize_t size;
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struct shmmap_entry *shmmap_se;
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shmseg = shm_find_segment_by_shmid(shmid, findremoved);
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if (shmseg == NULL)
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return EINVAL;
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error = ipcperm(cred, &shmseg->shm_perm,
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(shmflg & SHM_RDONLY) ? IPC_R : IPC_R|IPC_W);
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if (error)
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return error;
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shmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
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if (shmmap_s && shmmap_s->nitems >= shminfo.shmseg)
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return EMFILE;
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size = (shmseg->shm_segsz + PGOFSET) & ~PGOFSET;
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prot = VM_PROT_READ;
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if ((shmflg & SHM_RDONLY) == 0)
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prot |= VM_PROT_WRITE;
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flags = MAP_ANON | MAP_SHARED;
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if (shmaddr) {
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flags |= MAP_FIXED;
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if (shmflg & SHM_RND)
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attach_va =
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(vaddr_t)shmaddr & ~(SHMLBA-1);
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else if (((vaddr_t)shmaddr & (SHMLBA-1)) == 0)
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attach_va = (vaddr_t)shmaddr;
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else
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return EINVAL;
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} else {
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/* This is just a hint to uvm_mmap() about where to put it. */
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attach_va = VM_DEFAULT_ADDRESS(p->p_vmspace->vm_daddr, size);
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}
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shm_handle = shmseg->_shm_internal;
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uao_reference(shm_handle->shm_object);
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error = uvm_map(&p->p_vmspace->vm_map, &attach_va, size,
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shm_handle->shm_object, 0, 0,
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UVM_MAPFLAG(prot, prot, UVM_INH_SHARE, UVM_ADV_RANDOM, 0));
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if (error) {
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return error;
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}
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shmmap_se = pool_get(&shmmap_entry_pool, PR_WAITOK);
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shmmap_se->va = attach_va;
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shmmap_se->shmid = shmid;
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shmmap_s = shmmap_getprivate(p);
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#ifdef SHMDEBUG
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printf("shmat: vm %p: add %d @%lx\n", p->p_vmspace, shmid, attach_va);
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#endif
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SLIST_INSERT_HEAD(&shmmap_s->entries, shmmap_se, next);
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shmmap_s->nitems++;
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shmseg->shm_lpid = p->p_pid;
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shmseg->shm_atime = time.tv_sec;
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shmseg->shm_nattch++;
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*attachp = attach_va;
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return 0;
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}
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int
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sys___shmctl13(l, v, retval)
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struct lwp *l;
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void *v;
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register_t *retval;
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{
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struct sys___shmctl13_args /* {
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syscallarg(int) shmid;
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syscallarg(int) cmd;
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syscallarg(struct shmid_ds *) buf;
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} */ *uap = v;
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struct proc *p = l->l_proc;
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struct shmid_ds shmbuf;
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int cmd, error;
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cmd = SCARG(uap, cmd);
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if (cmd == IPC_SET) {
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error = copyin(SCARG(uap, buf), &shmbuf, sizeof(shmbuf));
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if (error)
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return (error);
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}
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error = shmctl1(p, SCARG(uap, shmid), cmd,
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(cmd == IPC_SET || cmd == IPC_STAT) ? &shmbuf : NULL);
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if (error == 0 && cmd == IPC_STAT)
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error = copyout(&shmbuf, SCARG(uap, buf), sizeof(shmbuf));
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return (error);
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}
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int
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shmctl1(p, shmid, cmd, shmbuf)
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struct proc *p;
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int shmid;
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int cmd;
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struct shmid_ds *shmbuf;
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{
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struct ucred *cred = p->p_ucred;
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struct shmid_ds *shmseg;
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int error = 0;
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shmseg = shm_find_segment_by_shmid(shmid, 0);
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if (shmseg == NULL)
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return EINVAL;
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switch (cmd) {
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case IPC_STAT:
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if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_R)) != 0)
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return error;
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memcpy(shmbuf, shmseg, sizeof(struct shmid_ds));
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break;
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case IPC_SET:
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if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
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return error;
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shmseg->shm_perm.uid = shmbuf->shm_perm.uid;
|
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shmseg->shm_perm.gid = shmbuf->shm_perm.gid;
|
|
shmseg->shm_perm.mode =
|
|
(shmseg->shm_perm.mode & ~ACCESSPERMS) |
|
|
(shmbuf->shm_perm.mode & ACCESSPERMS);
|
|
shmseg->shm_ctime = time.tv_sec;
|
|
break;
|
|
case IPC_RMID:
|
|
if ((error = ipcperm(cred, &shmseg->shm_perm, IPC_M)) != 0)
|
|
return error;
|
|
shmseg->shm_perm._key = IPC_PRIVATE;
|
|
shmseg->shm_perm.mode |= SHMSEG_REMOVED;
|
|
if (shmseg->shm_nattch <= 0) {
|
|
shm_deallocate_segment(shmseg);
|
|
shm_last_free = IPCID_TO_IX(shmid);
|
|
}
|
|
break;
|
|
case SHM_LOCK:
|
|
case SHM_UNLOCK:
|
|
default:
|
|
return EINVAL;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
shmget_existing(p, uap, mode, segnum, retval)
|
|
struct proc *p;
|
|
struct sys_shmget_args /* {
|
|
syscallarg(key_t) key;
|
|
syscallarg(size_t) size;
|
|
syscallarg(int) shmflg;
|
|
} */ *uap;
|
|
int mode;
|
|
int segnum;
|
|
register_t *retval;
|
|
{
|
|
struct shmid_ds *shmseg;
|
|
struct ucred *cred = p->p_ucred;
|
|
int error;
|
|
|
|
shmseg = &shmsegs[segnum];
|
|
if (shmseg->shm_perm.mode & SHMSEG_REMOVED) {
|
|
/*
|
|
* This segment is in the process of being allocated. Wait
|
|
* until it's done, and look the key up again (in case the
|
|
* allocation failed or it was freed).
|
|
*/
|
|
shmseg->shm_perm.mode |= SHMSEG_WANTED;
|
|
error = tsleep((caddr_t)shmseg, PLOCK | PCATCH, "shmget", 0);
|
|
if (error)
|
|
return error;
|
|
return EAGAIN;
|
|
}
|
|
if ((error = ipcperm(cred, &shmseg->shm_perm, mode)) != 0)
|
|
return error;
|
|
if (SCARG(uap, size) && SCARG(uap, size) > shmseg->shm_segsz)
|
|
return EINVAL;
|
|
if ((SCARG(uap, shmflg) & (IPC_CREAT | IPC_EXCL)) ==
|
|
(IPC_CREAT | IPC_EXCL))
|
|
return EEXIST;
|
|
*retval = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
shmget_allocate_segment(p, uap, mode, retval)
|
|
struct proc *p;
|
|
struct sys_shmget_args /* {
|
|
syscallarg(key_t) key;
|
|
syscallarg(size_t) size;
|
|
syscallarg(int) shmflg;
|
|
} */ *uap;
|
|
int mode;
|
|
register_t *retval;
|
|
{
|
|
int i, segnum, shmid, size;
|
|
struct ucred *cred = p->p_ucred;
|
|
struct shmid_ds *shmseg;
|
|
struct shm_handle *shm_handle;
|
|
int error = 0;
|
|
|
|
if (SCARG(uap, size) < shminfo.shmmin ||
|
|
SCARG(uap, size) > shminfo.shmmax)
|
|
return EINVAL;
|
|
if (shm_nused >= shminfo.shmmni) /* any shmids left? */
|
|
return ENOSPC;
|
|
size = (SCARG(uap, size) + PGOFSET) & ~PGOFSET;
|
|
if (shm_committed + btoc(size) > shminfo.shmall)
|
|
return ENOMEM;
|
|
if (shm_last_free < 0) {
|
|
for (i = 0; i < shminfo.shmmni; i++)
|
|
if (shmsegs[i].shm_perm.mode & SHMSEG_FREE)
|
|
break;
|
|
if (i == shminfo.shmmni)
|
|
panic("shmseg free count inconsistent");
|
|
segnum = i;
|
|
} else {
|
|
segnum = shm_last_free;
|
|
shm_last_free = -1;
|
|
}
|
|
shmseg = &shmsegs[segnum];
|
|
/*
|
|
* In case we sleep in malloc(), mark the segment present but deleted
|
|
* so that noone else tries to create the same key.
|
|
*/
|
|
shmseg->shm_perm.mode = SHMSEG_ALLOCATED | SHMSEG_REMOVED;
|
|
shmseg->shm_perm._key = SCARG(uap, key);
|
|
shmseg->shm_perm._seq = (shmseg->shm_perm._seq + 1) & 0x7fff;
|
|
shm_handle = (struct shm_handle *)
|
|
malloc(sizeof(struct shm_handle), M_SHM, M_WAITOK);
|
|
shmid = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
|
|
|
|
shm_handle->shm_object = uao_create(size, 0);
|
|
|
|
shmseg->_shm_internal = shm_handle;
|
|
shmseg->shm_perm.cuid = shmseg->shm_perm.uid = cred->cr_uid;
|
|
shmseg->shm_perm.cgid = shmseg->shm_perm.gid = cred->cr_gid;
|
|
shmseg->shm_perm.mode = (shmseg->shm_perm.mode & SHMSEG_WANTED) |
|
|
(mode & ACCESSPERMS) | SHMSEG_ALLOCATED;
|
|
shmseg->shm_segsz = SCARG(uap, size);
|
|
shmseg->shm_cpid = p->p_pid;
|
|
shmseg->shm_lpid = shmseg->shm_nattch = 0;
|
|
shmseg->shm_atime = shmseg->shm_dtime = 0;
|
|
shmseg->shm_ctime = time.tv_sec;
|
|
shm_committed += btoc(size);
|
|
shm_nused++;
|
|
|
|
*retval = shmid;
|
|
if (shmseg->shm_perm.mode & SHMSEG_WANTED) {
|
|
/*
|
|
* Somebody else wanted this key while we were asleep. Wake
|
|
* them up now.
|
|
*/
|
|
shmseg->shm_perm.mode &= ~SHMSEG_WANTED;
|
|
wakeup((caddr_t)shmseg);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
int
|
|
sys_shmget(l, v, retval)
|
|
struct lwp *l;
|
|
void *v;
|
|
register_t *retval;
|
|
{
|
|
struct sys_shmget_args /* {
|
|
syscallarg(key_t) key;
|
|
syscallarg(int) size;
|
|
syscallarg(int) shmflg;
|
|
} */ *uap = v;
|
|
struct proc *p = l->l_proc;
|
|
int segnum, mode, error;
|
|
|
|
mode = SCARG(uap, shmflg) & ACCESSPERMS;
|
|
if (SCARG(uap, key) != IPC_PRIVATE) {
|
|
again:
|
|
segnum = shm_find_segment_by_key(SCARG(uap, key));
|
|
if (segnum >= 0) {
|
|
error = shmget_existing(p, uap, mode, segnum, retval);
|
|
if (error == EAGAIN)
|
|
goto again;
|
|
return error;
|
|
}
|
|
if ((SCARG(uap, shmflg) & IPC_CREAT) == 0)
|
|
return ENOENT;
|
|
}
|
|
return shmget_allocate_segment(p, uap, mode, retval);
|
|
}
|
|
|
|
void
|
|
shmfork(vm1, vm2)
|
|
struct vmspace *vm1, *vm2;
|
|
{
|
|
struct shmmap_state *shmmap_s;
|
|
struct shmmap_entry *shmmap_se;
|
|
|
|
vm2->vm_shm = vm1->vm_shm;
|
|
|
|
if (vm1->vm_shm == NULL)
|
|
return;
|
|
|
|
#ifdef SHMDEBUG
|
|
printf("shmfork %p->%p\n", vm1, vm2);
|
|
#endif
|
|
|
|
shmmap_s = (struct shmmap_state *)vm1->vm_shm;
|
|
|
|
SLIST_FOREACH(shmmap_se, &shmmap_s->entries, next)
|
|
shmsegs[IPCID_TO_IX(shmmap_se->shmid)].shm_nattch++;
|
|
shmmap_s->nrefs++;
|
|
}
|
|
|
|
void
|
|
shmexit(vm)
|
|
struct vmspace *vm;
|
|
{
|
|
struct shmmap_state *shmmap_s;
|
|
struct shmmap_entry *shmmap_se;
|
|
|
|
shmmap_s = (struct shmmap_state *)vm->vm_shm;
|
|
if (shmmap_s == NULL)
|
|
return;
|
|
|
|
vm->vm_shm = NULL;
|
|
|
|
if (--shmmap_s->nrefs > 0) {
|
|
#ifdef SHMDEBUG
|
|
printf("shmexit: vm %p drop ref (%d entries), now used by %d\n",
|
|
vm, shmmap_s->nitems, shmmap_s->nrefs);
|
|
#endif
|
|
SLIST_FOREACH(shmmap_se, &shmmap_s->entries, next)
|
|
shmsegs[IPCID_TO_IX(shmmap_se->shmid)].shm_nattch--;
|
|
return;
|
|
}
|
|
|
|
#ifdef SHMDEBUG
|
|
printf("shmexit: vm %p cleanup (%d entries)\n", vm, shmmap_s->nitems);
|
|
#endif
|
|
while (!SLIST_EMPTY(&shmmap_s->entries)) {
|
|
shmmap_se = SLIST_FIRST(&shmmap_s->entries);
|
|
shm_delete_mapping(vm, shmmap_s, shmmap_se);
|
|
}
|
|
KASSERT(shmmap_s->nitems == 0);
|
|
free(shmmap_s, M_SHM);
|
|
}
|
|
|
|
void
|
|
shminit()
|
|
{
|
|
int i;
|
|
|
|
shminfo.shmmax *= PAGE_SIZE;
|
|
|
|
for (i = 0; i < shminfo.shmmni; i++) {
|
|
shmsegs[i].shm_perm.mode = SHMSEG_FREE;
|
|
shmsegs[i].shm_perm._seq = 0;
|
|
}
|
|
shm_last_free = 0;
|
|
shm_nused = 0;
|
|
shm_committed = 0;
|
|
|
|
pool_init(&shmmap_entry_pool, sizeof(struct shmmap_entry), 0, 0, 0,
|
|
"shmmp", 0);
|
|
}
|