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06cb725951
that call vnode_pager_alloc() so that a failure return can be dealt with. This fixes a panic seen on NFS clients when a file being opened is deleted on the server before the open completes.
839 lines
19 KiB
C
839 lines
19 KiB
C
/*
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* Copyright (c) 1988 University of Utah.
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* Copyright (c) 1991, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* the Systems Programming Group of the University of Utah Computer
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* Science Department.
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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 University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
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*
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* @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94
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* $Id: vm_mmap.c,v 1.24 1995/05/30 08:16:09 rgrimes Exp $
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*/
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/*
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* Mapped file (mmap) interface to VM
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/filedesc.h>
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#include <sys/resourcevar.h>
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#include <sys/proc.h>
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#include <sys/vnode.h>
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#include <sys/file.h>
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#include <sys/mman.h>
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#include <sys/conf.h>
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#include <miscfs/specfs/specdev.h>
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#include <vm/vm.h>
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#include <vm/vm_pager.h>
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#include <vm/vm_pageout.h>
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#include <vm/vm_prot.h>
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#ifdef DEBUG
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int mmapdebug;
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#define MDB_FOLLOW 0x01
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#define MDB_SYNC 0x02
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#define MDB_MAPIT 0x04
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#endif
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void pmap_object_init_pt();
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struct sbrk_args {
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int incr;
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};
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/* ARGSUSED */
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int
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sbrk(p, uap, retval)
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struct proc *p;
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struct sbrk_args *uap;
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int *retval;
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{
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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struct sstk_args {
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int incr;
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};
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/* ARGSUSED */
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int
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sstk(p, uap, retval)
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struct proc *p;
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struct sstk_args *uap;
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int *retval;
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{
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
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struct getpagesize_args {
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int dummy;
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};
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/* ARGSUSED */
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int
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ogetpagesize(p, uap, retval)
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struct proc *p;
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struct getpagesize_args *uap;
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int *retval;
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{
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*retval = PAGE_SIZE;
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return (0);
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}
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#endif /* COMPAT_43 || COMPAT_SUNOS */
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struct mmap_args {
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caddr_t addr;
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size_t len;
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int prot;
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int flags;
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int fd;
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long pad;
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off_t pos;
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};
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int
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mmap(p, uap, retval)
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struct proc *p;
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register struct mmap_args *uap;
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int *retval;
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{
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register struct filedesc *fdp = p->p_fd;
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register struct file *fp;
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struct vnode *vp;
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vm_offset_t addr;
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vm_size_t size;
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vm_prot_t prot, maxprot;
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caddr_t handle;
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int flags, error;
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prot = uap->prot & VM_PROT_ALL;
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flags = uap->flags;
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("mmap(%d): addr %x len %x pro %x flg %x fd %d pos %x\n",
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p->p_pid, uap->addr, uap->len, prot,
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flags, uap->fd, (vm_offset_t) uap->pos);
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#endif
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/*
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* Address (if FIXED) must be page aligned. Size is implicitly rounded
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* to a page boundary.
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*/
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addr = (vm_offset_t) uap->addr;
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if (((flags & MAP_FIXED) && (addr & PAGE_MASK)) ||
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(ssize_t) uap->len < 0 || ((flags & MAP_ANON) && uap->fd != -1))
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return (EINVAL);
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size = (vm_size_t) round_page(uap->len);
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/*
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* Check for illegal addresses. Watch out for address wrap... Note
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* that VM_*_ADDRESS are not constants due to casts (argh).
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*/
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if (flags & MAP_FIXED) {
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if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
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return (EINVAL);
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#ifndef i386
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if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
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return (EINVAL);
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#endif
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if (addr + size < addr)
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return (EINVAL);
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}
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/*
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* XXX if no hint provided for a non-fixed mapping place it after the
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* end of the largest possible heap.
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*
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* There should really be a pmap call to determine a reasonable location.
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*/
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if (addr == 0 && (flags & MAP_FIXED) == 0)
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addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
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if (flags & MAP_ANON) {
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/*
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* Mapping blank space is trivial.
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*/
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handle = NULL;
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maxprot = VM_PROT_ALL;
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} else {
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/*
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* Mapping file, get fp for validation. Obtain vnode and make
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* sure it is of appropriate type.
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*/
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if (((unsigned) uap->fd) >= fdp->fd_nfiles ||
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(fp = fdp->fd_ofiles[uap->fd]) == NULL)
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return (EBADF);
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if (fp->f_type != DTYPE_VNODE)
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return (EINVAL);
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vp = (struct vnode *) fp->f_data;
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if (vp->v_type != VREG && vp->v_type != VCHR)
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return (EINVAL);
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/*
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* XXX hack to handle use of /dev/zero to map anon memory (ala
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* SunOS).
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*/
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if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
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handle = NULL;
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maxprot = VM_PROT_ALL;
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flags |= MAP_ANON;
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} else {
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/*
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* Ensure that file and memory protections are
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* compatible. Note that we only worry about
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* writability if mapping is shared; in this case,
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* current and max prot are dictated by the open file.
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* XXX use the vnode instead? Problem is: what
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* credentials do we use for determination? What if
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* proc does a setuid?
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*/
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maxprot = VM_PROT_EXECUTE; /* ??? */
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if (fp->f_flag & FREAD)
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maxprot |= VM_PROT_READ;
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else if (prot & PROT_READ)
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return (EACCES);
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if (flags & MAP_SHARED) {
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if (fp->f_flag & FWRITE)
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maxprot |= VM_PROT_WRITE;
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else if (prot & PROT_WRITE)
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return (EACCES);
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} else
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maxprot |= VM_PROT_WRITE;
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handle = (caddr_t) vp;
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}
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}
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error = vm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
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flags, handle, (vm_offset_t) uap->pos);
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if (error == 0)
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*retval = (int) addr;
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return (error);
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}
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#ifdef COMPAT_43
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struct ommap_args {
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caddr_t addr;
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int len;
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int prot;
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int flags;
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int fd;
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long pos;
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};
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int
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ommap(p, uap, retval)
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struct proc *p;
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register struct ommap_args *uap;
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int *retval;
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{
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struct mmap_args nargs;
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static const char cvtbsdprot[8] = {
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0,
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PROT_EXEC,
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PROT_WRITE,
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PROT_EXEC | PROT_WRITE,
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PROT_READ,
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PROT_EXEC | PROT_READ,
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PROT_WRITE | PROT_READ,
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PROT_EXEC | PROT_WRITE | PROT_READ,
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};
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#define OMAP_ANON 0x0002
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#define OMAP_COPY 0x0020
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#define OMAP_SHARED 0x0010
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#define OMAP_FIXED 0x0100
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#define OMAP_INHERIT 0x0800
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nargs.addr = uap->addr;
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nargs.len = uap->len;
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nargs.prot = cvtbsdprot[uap->prot & 0x7];
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nargs.flags = 0;
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if (uap->flags & OMAP_ANON)
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nargs.flags |= MAP_ANON;
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if (uap->flags & OMAP_COPY)
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nargs.flags |= MAP_COPY;
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if (uap->flags & OMAP_SHARED)
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nargs.flags |= MAP_SHARED;
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else
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nargs.flags |= MAP_PRIVATE;
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if (uap->flags & OMAP_FIXED)
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nargs.flags |= MAP_FIXED;
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if (uap->flags & OMAP_INHERIT)
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nargs.flags |= MAP_INHERIT;
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nargs.fd = uap->fd;
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nargs.pos = uap->pos;
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return (mmap(p, &nargs, retval));
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}
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#endif /* COMPAT_43 */
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struct msync_args {
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caddr_t addr;
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int len;
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int flags;
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};
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int
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msync(p, uap, retval)
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struct proc *p;
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struct msync_args *uap;
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int *retval;
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{
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vm_offset_t addr;
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vm_size_t size;
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int flags;
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vm_map_t map;
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int rv;
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#ifdef DEBUG
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if (mmapdebug & (MDB_FOLLOW | MDB_SYNC))
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printf("msync(%d): addr %x len %x\n",
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p->p_pid, uap->addr, uap->len);
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#endif
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map = &p->p_vmspace->vm_map;
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addr = (vm_offset_t) uap->addr;
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size = (vm_size_t) uap->len;
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flags = uap->flags;
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if (((int) addr & PAGE_MASK) || addr + size < addr ||
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(flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE))
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return (EINVAL);
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/*
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* XXX Gak! If size is zero we are supposed to sync "all modified
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* pages with the region containing addr". Unfortunately, we don't
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* really keep track of individual mmaps so we approximate by flushing
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* the range of the map entry containing addr. This can be incorrect
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* if the region splits or is coalesced with a neighbor.
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*/
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if (size == 0) {
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vm_map_entry_t entry;
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vm_map_lock_read(map);
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rv = vm_map_lookup_entry(map, addr, &entry);
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vm_map_unlock_read(map);
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if (rv == FALSE)
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return (EINVAL);
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addr = entry->start;
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size = entry->end - entry->start;
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}
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#ifdef DEBUG
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if (mmapdebug & MDB_SYNC)
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printf("msync: cleaning/flushing address range [%x-%x)\n",
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addr, addr + size);
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#endif
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/*
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* Clean the pages and interpret the return value.
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*/
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rv = vm_map_clean(map, addr, addr + size, (flags & MS_ASYNC) == 0,
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(flags & MS_INVALIDATE) != 0);
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switch (rv) {
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case KERN_SUCCESS:
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break;
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case KERN_INVALID_ADDRESS:
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return (EINVAL); /* Sun returns ENOMEM? */
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case KERN_FAILURE:
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return (EIO);
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default:
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return (EINVAL);
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}
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return (0);
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}
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struct munmap_args {
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caddr_t addr;
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int len;
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};
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int
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munmap(p, uap, retval)
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register struct proc *p;
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register struct munmap_args *uap;
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int *retval;
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{
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vm_offset_t addr;
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vm_size_t size;
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vm_map_t map;
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("munmap(%d): addr %x len %x\n",
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p->p_pid, uap->addr, uap->len);
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#endif
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addr = (vm_offset_t) uap->addr;
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if ((addr & PAGE_MASK) || uap->len < 0)
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return (EINVAL);
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size = (vm_size_t) round_page(uap->len);
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if (size == 0)
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return (0);
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/*
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* Check for illegal addresses. Watch out for address wrap... Note
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* that VM_*_ADDRESS are not constants due to casts (argh).
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*/
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if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
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return (EINVAL);
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#ifndef i386
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if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
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return (EINVAL);
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#endif
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if (addr + size < addr)
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return (EINVAL);
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map = &p->p_vmspace->vm_map;
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/*
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* Make sure entire range is allocated.
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*/
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if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE))
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return (EINVAL);
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/* returns nothing but KERN_SUCCESS anyway */
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(void) vm_map_remove(map, addr, addr + size);
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return (0);
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}
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void
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munmapfd(p, fd)
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struct proc *p;
|
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int fd;
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{
|
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("munmapfd(%d): fd %d\n", p->p_pid, fd);
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#endif
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/*
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|
* XXX should unmap any regions mapped to this file
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|
*/
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p->p_fd->fd_ofileflags[fd] &= ~UF_MAPPED;
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}
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struct mprotect_args {
|
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caddr_t addr;
|
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int len;
|
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int prot;
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};
|
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int
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mprotect(p, uap, retval)
|
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struct proc *p;
|
|
struct mprotect_args *uap;
|
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int *retval;
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{
|
|
vm_offset_t addr;
|
|
vm_size_t size;
|
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register vm_prot_t prot;
|
|
|
|
#ifdef DEBUG
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|
if (mmapdebug & MDB_FOLLOW)
|
|
printf("mprotect(%d): addr %x len %x prot %d\n",
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p->p_pid, uap->addr, uap->len, uap->prot);
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#endif
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addr = (vm_offset_t) uap->addr;
|
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if ((addr & PAGE_MASK) || uap->len < 0)
|
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return (EINVAL);
|
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size = (vm_size_t) uap->len;
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prot = uap->prot & VM_PROT_ALL;
|
|
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|
switch (vm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot,
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FALSE)) {
|
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case KERN_SUCCESS:
|
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return (0);
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|
case KERN_PROTECTION_FAILURE:
|
|
return (EACCES);
|
|
}
|
|
return (EINVAL);
|
|
}
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|
|
|
struct madvise_args {
|
|
caddr_t addr;
|
|
int len;
|
|
int behav;
|
|
};
|
|
|
|
/* ARGSUSED */
|
|
int
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|
madvise(p, uap, retval)
|
|
struct proc *p;
|
|
struct madvise_args *uap;
|
|
int *retval;
|
|
{
|
|
|
|
/* Not yet implemented */
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
struct mincore_args {
|
|
caddr_t addr;
|
|
int len;
|
|
char *vec;
|
|
};
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|
|
|
/* ARGSUSED */
|
|
int
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|
mincore(p, uap, retval)
|
|
struct proc *p;
|
|
struct mincore_args *uap;
|
|
int *retval;
|
|
{
|
|
|
|
/* Not yet implemented */
|
|
return (EOPNOTSUPP);
|
|
}
|
|
|
|
struct mlock_args {
|
|
caddr_t addr;
|
|
size_t len;
|
|
};
|
|
int
|
|
mlock(p, uap, retval)
|
|
struct proc *p;
|
|
struct mlock_args *uap;
|
|
int *retval;
|
|
{
|
|
vm_offset_t addr;
|
|
vm_size_t size;
|
|
int error;
|
|
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_FOLLOW)
|
|
printf("mlock(%d): addr %x len %x\n",
|
|
p->p_pid, uap->addr, uap->len);
|
|
#endif
|
|
addr = (vm_offset_t) uap->addr;
|
|
if ((addr & PAGE_MASK) || uap->addr + uap->len < uap->addr)
|
|
return (EINVAL);
|
|
size = round_page((vm_size_t) uap->len);
|
|
if (atop(size) + cnt.v_wire_count > vm_page_max_wired)
|
|
return (EAGAIN);
|
|
#ifdef pmap_wired_count
|
|
if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) >
|
|
p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur)
|
|
return (EAGAIN);
|
|
#else
|
|
error = suser(p->p_ucred, &p->p_acflag);
|
|
if (error)
|
|
return (error);
|
|
#endif
|
|
|
|
error = vm_map_pageable(&p->p_vmspace->vm_map, addr, addr + size, FALSE);
|
|
return (error == KERN_SUCCESS ? 0 : ENOMEM);
|
|
}
|
|
|
|
struct munlock_args {
|
|
caddr_t addr;
|
|
size_t len;
|
|
};
|
|
int
|
|
munlock(p, uap, retval)
|
|
struct proc *p;
|
|
struct munlock_args *uap;
|
|
int *retval;
|
|
{
|
|
vm_offset_t addr;
|
|
vm_size_t size;
|
|
int error;
|
|
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_FOLLOW)
|
|
printf("munlock(%d): addr %x len %x\n",
|
|
p->p_pid, uap->addr, uap->len);
|
|
#endif
|
|
addr = (vm_offset_t) uap->addr;
|
|
if ((addr & PAGE_MASK) || uap->addr + uap->len < uap->addr)
|
|
return (EINVAL);
|
|
#ifndef pmap_wired_count
|
|
error = suser(p->p_ucred, &p->p_acflag);
|
|
if (error)
|
|
return (error);
|
|
#endif
|
|
size = round_page((vm_size_t) uap->len);
|
|
|
|
error = vm_map_pageable(&p->p_vmspace->vm_map, addr, addr + size, TRUE);
|
|
return (error == KERN_SUCCESS ? 0 : ENOMEM);
|
|
}
|
|
|
|
/*
|
|
* Internal version of mmap.
|
|
* Currently used by mmap, exec, and sys5 shared memory.
|
|
* Handle is either a vnode pointer or NULL for MAP_ANON.
|
|
*/
|
|
int
|
|
vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
|
|
register vm_map_t map;
|
|
register vm_offset_t *addr;
|
|
register vm_size_t size;
|
|
vm_prot_t prot, maxprot;
|
|
register int flags;
|
|
caddr_t handle; /* XXX should be vp */
|
|
vm_offset_t foff;
|
|
{
|
|
register vm_pager_t pager;
|
|
boolean_t fitit;
|
|
vm_object_t object;
|
|
struct vnode *vp = NULL;
|
|
int type;
|
|
int rv = KERN_SUCCESS;
|
|
vm_size_t objsize;
|
|
struct proc *p = curproc;
|
|
|
|
if (size == 0)
|
|
return (0);
|
|
|
|
objsize = size = round_page(size);
|
|
|
|
/*
|
|
* We currently can only deal with page aligned file offsets.
|
|
* The check is here rather than in the syscall because the
|
|
* kernel calls this function internally for other mmaping
|
|
* operations (such as in exec) and non-aligned offsets will
|
|
* cause pmap inconsistencies...so we want to be sure to
|
|
* disallow this in all cases.
|
|
*/
|
|
if (foff & PAGE_MASK)
|
|
return (EINVAL);
|
|
|
|
if ((flags & MAP_FIXED) == 0) {
|
|
fitit = TRUE;
|
|
*addr = round_page(*addr);
|
|
} else {
|
|
if (*addr != trunc_page(*addr))
|
|
return (EINVAL);
|
|
fitit = FALSE;
|
|
(void) vm_map_remove(map, *addr, *addr + size);
|
|
}
|
|
|
|
/*
|
|
* Lookup/allocate pager. All except an unnamed anonymous lookup gain
|
|
* a reference to ensure continued existance of the object. (XXX the
|
|
* exception is to appease the pageout daemon)
|
|
*/
|
|
if (flags & MAP_ANON) {
|
|
type = PG_DFLT;
|
|
/*
|
|
* Unnamed anonymous regions always start at 0.
|
|
*/
|
|
if (handle == 0)
|
|
foff = 0;
|
|
} else {
|
|
vp = (struct vnode *) handle;
|
|
if (vp->v_type == VCHR) {
|
|
type = PG_DEVICE;
|
|
handle = (caddr_t) vp->v_rdev;
|
|
} else {
|
|
struct vattr vat;
|
|
int error;
|
|
|
|
error = VOP_GETATTR(vp, &vat, p->p_ucred, p);
|
|
if (error)
|
|
return (error);
|
|
objsize = vat.va_size;
|
|
type = PG_VNODE;
|
|
}
|
|
}
|
|
pager = vm_pager_allocate(type, handle, objsize, prot, foff);
|
|
if (pager == NULL)
|
|
return (type == PG_DEVICE ? EINVAL : ENOMEM);
|
|
/*
|
|
* Guarantee that the pager has an object.
|
|
*/
|
|
object = vm_object_lookup(pager);
|
|
if (object == NULL) {
|
|
if (handle != NULL)
|
|
panic("vm_mmap: pager didn't allocate an object (and should have)");
|
|
/*
|
|
* Should only happen for unnamed anonymous regions.
|
|
*/
|
|
object = vm_object_allocate(size);
|
|
object->pager = pager;
|
|
} else {
|
|
/*
|
|
* Lose vm_object_lookup() reference. Retain reference
|
|
* gained by vm_pager_allocate().
|
|
*/
|
|
vm_object_deallocate(object);
|
|
}
|
|
/*
|
|
* At this point, our actions above have gained a total of
|
|
* one reference to the object, and we have a pager.
|
|
*/
|
|
|
|
/*
|
|
* Anonymous memory, shared file, or character special file.
|
|
*/
|
|
if ((flags & (MAP_ANON|MAP_SHARED)) || (type == PG_DEVICE)) {
|
|
rv = vm_map_find(map, object, foff, addr, size, fitit);
|
|
if (rv != KERN_SUCCESS) {
|
|
/*
|
|
* Lose the object reference. This will also destroy
|
|
* the pager if there are no other references.
|
|
*/
|
|
vm_object_deallocate(object);
|
|
goto out;
|
|
}
|
|
}
|
|
/*
|
|
* mmap a COW regular file
|
|
*/
|
|
else {
|
|
vm_map_t tmap;
|
|
vm_offset_t off;
|
|
vm_map_entry_t entry;
|
|
|
|
if (flags & MAP_COPY) {
|
|
/* locate and allocate the target address space */
|
|
rv = vm_map_find(map, NULL, 0, addr, size, fitit);
|
|
if (rv != KERN_SUCCESS) {
|
|
vm_object_deallocate(object);
|
|
goto out;
|
|
}
|
|
|
|
off = VM_MIN_ADDRESS;
|
|
tmap = vm_map_create(NULL, off, off + size, TRUE);
|
|
rv = vm_map_find(tmap, object, foff, &off, size, FALSE);
|
|
if (rv != KERN_SUCCESS) {
|
|
/*
|
|
* Deallocate and delete the temporary map.
|
|
* Note that since the object insertion
|
|
* above has failed, the vm_map_deallocate
|
|
* doesn't lose the object reference - we
|
|
* must do it explicitly.
|
|
*/
|
|
vm_object_deallocate(object);
|
|
vm_map_deallocate(tmap);
|
|
goto out;
|
|
}
|
|
rv = vm_map_copy(map, tmap, *addr, size, off,
|
|
FALSE, FALSE);
|
|
/*
|
|
* Deallocate temporary map. XXX - depending
|
|
* on events, this may leave the object with
|
|
* no net gain in reference count! ...this
|
|
* needs to be looked at!
|
|
*/
|
|
vm_map_deallocate(tmap);
|
|
if (rv != KERN_SUCCESS)
|
|
goto out;
|
|
|
|
} else {
|
|
vm_object_t user_object;
|
|
|
|
/*
|
|
* Create a new object and make the original object
|
|
* the backing object. NOTE: the object reference gained
|
|
* above is now changed into the reference held by
|
|
* user_object. Since we don't map 'object', we want
|
|
* only this one reference.
|
|
*/
|
|
user_object = vm_object_allocate(object->size);
|
|
user_object->shadow = object;
|
|
TAILQ_INSERT_TAIL(&object->reverse_shadow_head,
|
|
user_object, reverse_shadow_list);
|
|
|
|
rv = vm_map_find(map, user_object, foff, addr, size, fitit);
|
|
if( rv != KERN_SUCCESS) {
|
|
vm_object_deallocate(user_object);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* this is a consistancy check, gets the map entry, and should
|
|
* never fail
|
|
*/
|
|
if (!vm_map_lookup_entry(map, *addr, &entry)) {
|
|
panic("vm_mmap: missing map entry!!!");
|
|
}
|
|
|
|
entry->copy_on_write = TRUE;
|
|
}
|
|
|
|
/*
|
|
* set pages COW and protect for read access only
|
|
*/
|
|
vm_object_pmap_copy(object, foff, foff + size);
|
|
|
|
}
|
|
|
|
/*
|
|
* "Pre-fault" resident pages.
|
|
*/
|
|
if ((type == PG_VNODE) && (map->pmap != NULL)) {
|
|
pmap_object_init_pt(map->pmap, *addr, object, foff, size);
|
|
}
|
|
|
|
/*
|
|
* Correct protection (default is VM_PROT_ALL). If maxprot is
|
|
* different than prot, we must set both explicitly.
|
|
*/
|
|
rv = KERN_SUCCESS;
|
|
if (maxprot != VM_PROT_ALL)
|
|
rv = vm_map_protect(map, *addr, *addr + size, maxprot, TRUE);
|
|
if (rv == KERN_SUCCESS && prot != maxprot)
|
|
rv = vm_map_protect(map, *addr, *addr + size, prot, FALSE);
|
|
if (rv != KERN_SUCCESS) {
|
|
(void) vm_map_remove(map, *addr, *addr + size);
|
|
goto out;
|
|
}
|
|
/*
|
|
* Shared memory is also shared with children.
|
|
*/
|
|
if (flags & MAP_SHARED) {
|
|
rv = vm_map_inherit(map, *addr, *addr + size, VM_INHERIT_SHARE);
|
|
if (rv != KERN_SUCCESS) {
|
|
(void) vm_map_remove(map, *addr, *addr + size);
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_MAPIT)
|
|
printf("vm_mmap: rv %d\n", rv);
|
|
#endif
|
|
switch (rv) {
|
|
case KERN_SUCCESS:
|
|
return (0);
|
|
case KERN_INVALID_ADDRESS:
|
|
case KERN_NO_SPACE:
|
|
return (ENOMEM);
|
|
case KERN_PROTECTION_FAILURE:
|
|
return (EACCES);
|
|
default:
|
|
return (EINVAL);
|
|
}
|
|
}
|