927 lines
23 KiB
C
927 lines
23 KiB
C
/* $NetBSD: vm_mmap.c,v 1.47 1996/03/16 23:15:23 christos Exp $ */
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/*
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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 8.5 (Berkeley) 5/19/94
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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 <sys/mount.h>
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#include <sys/syscallargs.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_prot.h>
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#ifdef DEBUG
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int mmapdebug = 0;
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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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/* ARGSUSED */
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int
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sys_sbrk(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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#if 0
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struct sys_sbrk_args /* {
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syscallarg(int) incr;
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} */ *uap = v;
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#endif
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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/* ARGSUSED */
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int
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sys_sstk(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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#if 0
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struct sys_sstk_args /* {
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syscallarg(int) incr;
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} */ *uap = v;
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#endif
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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/*
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* Memory Map (mmap) system call. Note that the file offset
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* and address are allowed to be NOT page aligned, though if
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* the MAP_FIXED flag it set, both must have the same remainder
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* modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not
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* page-aligned, the actual mapping starts at trunc_page(addr)
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* and the return value is adjusted up by the page offset.
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*/
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int
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sys_mmap(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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register struct sys_mmap_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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syscallarg(int) prot;
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syscallarg(int) flags;
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syscallarg(int) fd;
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syscallarg(long) pad;
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syscallarg(off_t) pos;
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} */ *uap = v;
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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, pos;
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vm_size_t size, pageoff;
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vm_prot_t prot, maxprot;
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caddr_t handle;
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int fd, flags, error;
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vm_offset_t vm_min_address = VM_MIN_ADDRESS;
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addr = (vm_offset_t) SCARG(uap, addr);
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size = (vm_size_t) SCARG(uap, len);
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prot = SCARG(uap, prot) & VM_PROT_ALL;
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flags = SCARG(uap, flags);
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fd = SCARG(uap, fd);
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pos = (vm_offset_t) SCARG(uap, pos);
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("mmap(%d): addr %lx len %lx pro %x flg %x fd %d pos %lx\n",
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p->p_pid, addr, size, prot, flags, fd, pos);
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#endif
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/*
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* Align the file position to a page boundary,
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* and save its page offset component.
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*/
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pageoff = (pos & PAGE_MASK);
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pos -= pageoff;
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/* Adjust size for rounding (on both ends). */
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size += pageoff; /* low end... */
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size = (vm_size_t) round_page(size); /* hi end */
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/* Do not allow mappings that cause address wrap... */
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if ((ssize_t)size < 0)
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return (EINVAL);
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/*
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* Check for illegal addresses. Watch out for address wrap...
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* Note 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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/*
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* The specified address must have the same remainder
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* as the file offset taken modulo PAGE_SIZE, so it
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* should be aligned after adjustment by pageoff.
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*/
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addr -= pageoff;
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if (addr & PAGE_MASK)
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return (EINVAL);
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/* Address range must be all in user VM space. */
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if (VM_MAXUSER_ADDRESS > 0 &&
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addr + size > VM_MAXUSER_ADDRESS)
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return (EINVAL);
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if (vm_min_address > 0 && addr < vm_min_address)
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return (EINVAL);
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if (addr > addr + size)
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return (EINVAL);
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}
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/*
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* XXX for non-fixed mappings where no hint is provided or
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* the hint would fall in the potential heap space,
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* place it after the 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
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* location. (To avoid VA cache alias problems, for example!)
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*/
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else if (addr < round_page(p->p_vmspace->vm_daddr + MAXDSIZ))
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addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
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if ((flags & MAP_ANON) == 0) {
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/*
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* Mapping file, get fp for validation.
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* Obtain vnode and make sure it is of appropriate type.
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*/
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if (((unsigned)fd) >= fdp->fd_nfiles ||
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(fp = fdp->fd_ofiles[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
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* memory (ala SunOS).
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*/
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if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
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flags |= MAP_ANON;
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goto is_anon;
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}
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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?
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* What if 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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} else {
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/*
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* (flags & MAP_ANON) == TRUE
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* Mapping blank space is trivial.
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*/
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if (fd != -1)
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return (EINVAL);
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is_anon:
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handle = NULL;
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maxprot = VM_PROT_ALL;
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pos = 0;
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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, pos);
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if (error == 0)
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*retval = (register_t)(addr + pageoff);
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return (error);
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}
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int
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sys_msync(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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struct sys_msync_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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} */ *uap = v;
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vm_offset_t addr;
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vm_size_t size, pageoff;
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vm_map_t map;
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int rv;
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boolean_t syncio, invalidate;
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addr = (vm_offset_t)SCARG(uap, addr);
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size = (vm_size_t)SCARG(uap, len);
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#ifdef DEBUG
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if (mmapdebug & (MDB_FOLLOW|MDB_SYNC))
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printf("msync(%d): addr %lx len %lx\n",
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p->p_pid, addr, size);
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#endif
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/*
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* Align the address to a page boundary,
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* and adjust the size accordingly.
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*/
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pageoff = (addr & PAGE_MASK);
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addr -= pageoff;
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size += pageoff;
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size = (vm_size_t) round_page(size);
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/* Disallow wrap-around. */
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if (addr + (int)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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* 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
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* don't really keep track of individual mmaps so we approximate
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* by flushing the range of the map entry containing addr.
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* This can be incorrect if the region splits or is coalesced
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* 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 [%lx-%lx)\n",
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addr, addr+size);
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#endif
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/*
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* Could pass this in as a third flag argument to implement
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* Sun's MS_ASYNC.
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*/
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syncio = TRUE;
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/*
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* XXX bummer, gotta flush all cached pages to ensure
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* consistency with the file system cache. Otherwise, we could
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* pass this in to implement Sun's MS_INVALIDATE.
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*/
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invalidate = TRUE;
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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, syncio, invalidate);
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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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int
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sys_munmap(p, v, retval)
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register struct proc *p;
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void *v;
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register_t *retval;
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{
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register struct sys_munmap_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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} */ *uap = v;
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vm_offset_t addr;
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vm_size_t size, pageoff;
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vm_map_t map;
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vm_offset_t vm_min_address = VM_MIN_ADDRESS;
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addr = (vm_offset_t) SCARG(uap, addr);
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size = (vm_size_t) SCARG(uap, len);
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("munmap(%d): addr %lx len %lx\n",
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p->p_pid, addr, size);
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#endif
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/*
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* Align the address to a page boundary,
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* and adjust the size accordingly.
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*/
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pageoff = (addr & PAGE_MASK);
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addr -= pageoff;
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size += pageoff;
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size = (vm_size_t) round_page(size);
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if ((int)size < 0)
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return(EINVAL);
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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...
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* Note 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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if (vm_min_address > 0 && addr < vm_min_address)
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return (EINVAL);
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if (addr > addr + size)
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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 vm_deallocate 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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int
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sys_mprotect(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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struct sys_mprotect_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(int) len;
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syscallarg(int) prot;
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} */ *uap = v;
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vm_offset_t addr;
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vm_size_t size, pageoff;
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register vm_prot_t prot;
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addr = (vm_offset_t)SCARG(uap, addr);
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size = (vm_size_t)SCARG(uap, len);
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prot = SCARG(uap, prot) & VM_PROT_ALL;
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("mprotect(%d): addr %lx len %lx prot %d\n", p->p_pid,
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addr, size, prot);
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#endif
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/*
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* Align the address to a page boundary,
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* and adjust the size accordingly.
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*/
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pageoff = (addr & PAGE_MASK);
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addr -= pageoff;
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size += pageoff;
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size = (vm_size_t) round_page(size);
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if ((int)size < 0)
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return(EINVAL);
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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:
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return (EACCES);
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}
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return (EINVAL);
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}
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/* ARGSUSED */
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int
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sys_madvise(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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#if 0
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struct sys_madvise_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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syscallarg(int) behav;
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} */ *uap = v;
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#endif
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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/* ARGSUSED */
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int
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sys_mincore(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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#if 0
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struct sys_mincore_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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syscallarg(char *) vec;
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} */ *uap = v;
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#endif
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/* Not yet implemented */
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return (EOPNOTSUPP);
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}
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int
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sys_mlock(p, v, retval)
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struct proc *p;
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void *v;
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register_t *retval;
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{
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struct sys_mlock_args /* {
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syscallarg(caddr_t) addr;
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syscallarg(size_t) len;
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} */ *uap = v;
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vm_offset_t addr;
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vm_size_t size, pageoff;
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int error;
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extern int vm_page_max_wired;
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addr = (vm_offset_t)SCARG(uap, addr);
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size = (vm_size_t)SCARG(uap, len);
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#ifdef DEBUG
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if (mmapdebug & MDB_FOLLOW)
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printf("mlock(%d): addr %lx len %lx\n",
|
|
p->p_pid, addr, size);
|
|
#endif
|
|
/*
|
|
* Align the address to a page boundary,
|
|
* and adjust the size accordingly.
|
|
*/
|
|
pageoff = (addr & PAGE_MASK);
|
|
addr -= pageoff;
|
|
size += pageoff;
|
|
size = (vm_size_t) round_page(size);
|
|
|
|
/* Disallow wrap-around. */
|
|
if (addr + (int)size < addr)
|
|
return (EINVAL);
|
|
|
|
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
|
|
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
|
|
return (error);
|
|
#endif
|
|
|
|
error = vm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, FALSE);
|
|
return (error == KERN_SUCCESS ? 0 : ENOMEM);
|
|
}
|
|
|
|
int
|
|
sys_munlock(p, v, retval)
|
|
struct proc *p;
|
|
void *v;
|
|
register_t *retval;
|
|
{
|
|
struct sys_munlock_args /* {
|
|
syscallarg(caddr_t) addr;
|
|
syscallarg(size_t) len;
|
|
} */ *uap = v;
|
|
vm_offset_t addr;
|
|
vm_size_t size, pageoff;
|
|
int error;
|
|
|
|
addr = (vm_offset_t)SCARG(uap, addr);
|
|
size = (vm_size_t)SCARG(uap, len);
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_FOLLOW)
|
|
printf("munlock(%d): addr %lx len %lx\n",
|
|
p->p_pid, addr, size);
|
|
#endif
|
|
/*
|
|
* Align the address to a page boundary,
|
|
* and adjust the size accordingly.
|
|
*/
|
|
pageoff = (addr & PAGE_MASK);
|
|
addr -= pageoff;
|
|
size += pageoff;
|
|
size = (vm_size_t) round_page(size);
|
|
|
|
/* Disallow wrap-around. */
|
|
if (addr + (int)size < addr)
|
|
return (EINVAL);
|
|
|
|
#ifndef pmap_wired_count
|
|
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
|
|
return (error);
|
|
#endif
|
|
|
|
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.
|
|
* This (internal) interface requires the file offset to be
|
|
* page-aligned by the caller. (Also addr, if MAP_FIXED).
|
|
*/
|
|
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;
|
|
|
|
if (size == 0)
|
|
return (0);
|
|
|
|
/* The file offset must be page aligned. */
|
|
if (foff & PAGE_MASK)
|
|
return (EINVAL);
|
|
|
|
if ((flags & MAP_FIXED) == 0) {
|
|
/* The address is just a hint */
|
|
fitit = TRUE;
|
|
*addr = round_page(*addr);
|
|
} else {
|
|
/*
|
|
* Use the specified address exactly
|
|
* (but check alignment first).
|
|
*/
|
|
fitit = FALSE;
|
|
if (*addr & PAGE_MASK)
|
|
return (EINVAL);
|
|
(void)vm_deallocate(map, *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;
|
|
foff = 0;
|
|
} else {
|
|
vp = (struct vnode *)handle;
|
|
if (vp->v_type == VCHR) {
|
|
type = PG_DEVICE;
|
|
handle = (caddr_t)(long)vp->v_rdev;
|
|
} else
|
|
type = PG_VNODE;
|
|
}
|
|
pager = vm_pager_allocate(type, handle, size, prot, foff);
|
|
if (pager == NULL)
|
|
return (type == PG_DEVICE ? EINVAL : ENOMEM);
|
|
/*
|
|
* Find object and release extra reference gained by lookup
|
|
*/
|
|
object = vm_object_lookup(pager);
|
|
vm_object_deallocate(object);
|
|
|
|
/*
|
|
* Anonymous memory.
|
|
*/
|
|
if (flags & MAP_ANON) {
|
|
rv = vm_allocate_with_pager(map, addr, size, fitit,
|
|
pager, foff, TRUE);
|
|
if (rv != KERN_SUCCESS) {
|
|
if (handle == NULL)
|
|
vm_pager_deallocate(pager);
|
|
else
|
|
vm_object_deallocate(object);
|
|
goto out;
|
|
}
|
|
/*
|
|
* Don't cache anonymous objects.
|
|
* Loses the reference gained by vm_pager_allocate.
|
|
* Note that object will be NULL when handle == NULL,
|
|
* this is ok since vm_allocate_with_pager has made
|
|
* sure that these objects are uncached.
|
|
*/
|
|
(void) pager_cache(object, FALSE);
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_MAPIT)
|
|
printf("vm_mmap(%d): ANON *addr %lx size %lx pager %p\n",
|
|
curproc->p_pid, *addr, size, pager);
|
|
#endif
|
|
}
|
|
/*
|
|
* Must be a mapped file.
|
|
* Distinguish between character special and regular files.
|
|
*/
|
|
else if (vp->v_type == VCHR) {
|
|
rv = vm_allocate_with_pager(map, addr, size, fitit,
|
|
pager, foff, FALSE);
|
|
/*
|
|
* Uncache the object and lose the reference gained
|
|
* by vm_pager_allocate(). If the call to
|
|
* vm_allocate_with_pager() was sucessful, then we
|
|
* gained an additional reference ensuring the object
|
|
* will continue to exist. If the call failed then
|
|
* the deallocate call below will terminate the
|
|
* object which is fine.
|
|
*/
|
|
(void) pager_cache(object, FALSE);
|
|
if (rv != KERN_SUCCESS)
|
|
goto out;
|
|
}
|
|
/*
|
|
* A regular file
|
|
*/
|
|
else {
|
|
#ifdef DEBUG
|
|
if (object == NULL)
|
|
printf("vm_mmap: no object: vp %p, pager %p\n",
|
|
vp, pager);
|
|
#endif
|
|
/*
|
|
* Map it directly.
|
|
* Allows modifications to go out to the vnode.
|
|
*/
|
|
if (flags & MAP_SHARED) {
|
|
rv = vm_allocate_with_pager(map, addr, size,
|
|
fitit, pager,
|
|
foff, FALSE);
|
|
if (rv != KERN_SUCCESS) {
|
|
vm_object_deallocate(object);
|
|
goto out;
|
|
}
|
|
/*
|
|
* Don't cache the object. This is the easiest way
|
|
* of ensuring that data gets back to the filesystem
|
|
* because vnode_pager_deallocate() will fsync the
|
|
* vnode. pager_cache() will lose the extra ref.
|
|
*/
|
|
if (prot & VM_PROT_WRITE)
|
|
pager_cache(object, FALSE);
|
|
else
|
|
vm_object_deallocate(object);
|
|
}
|
|
/*
|
|
* Copy-on-write of file. Two flavors.
|
|
* MAP_COPY is true COW, you essentially get a snapshot of
|
|
* the region at the time of mapping. MAP_PRIVATE means only
|
|
* that your changes are not reflected back to the object.
|
|
* Changes made by others will be seen.
|
|
*/
|
|
else {
|
|
vm_map_t tmap;
|
|
vm_offset_t off;
|
|
|
|
/* locate and allocate the target address space */
|
|
vm_map_lock(map);
|
|
if (fitit) {
|
|
/*
|
|
* Find space in the map at a location
|
|
* that is compatible with the object/offset
|
|
* we're going to attach there.
|
|
*/
|
|
again:
|
|
if (vm_map_findspace(map, *addr, size,
|
|
addr) == 1) {
|
|
rv = KERN_NO_SPACE;
|
|
} else {
|
|
#ifdef PMAP_PREFER
|
|
PMAP_PREFER(foff, addr);
|
|
#endif
|
|
rv = vm_map_insert(map, NULL,
|
|
(vm_offset_t)0,
|
|
*addr, *addr+size);
|
|
/*
|
|
* vm_map_insert() may fail if
|
|
* PMAP_PREFER() has altered
|
|
* the initial address.
|
|
* If so, we start again.
|
|
*/
|
|
if (rv == KERN_NO_SPACE)
|
|
goto again;
|
|
}
|
|
} else {
|
|
rv = vm_map_insert(map, NULL, (vm_offset_t)0,
|
|
*addr, *addr + size);
|
|
|
|
#ifdef DEBUG
|
|
/*
|
|
* Check against PMAP preferred address. If
|
|
* there's a mismatch, these pages should not
|
|
* be shared with others. <howto?>
|
|
*/
|
|
if (rv == KERN_SUCCESS &&
|
|
(mmapdebug & MDB_MAPIT)) {
|
|
vm_offset_t paddr = *addr;
|
|
#ifdef PMAP_PREFER
|
|
PMAP_PREFER(foff, &paddr);
|
|
#endif
|
|
if (paddr != *addr)
|
|
printf(
|
|
"vm_mmap: pmap botch! "
|
|
"[foff %lx, addr %lx, paddr %lx]\n",
|
|
foff, *addr, paddr);
|
|
}
|
|
#endif
|
|
}
|
|
vm_map_unlock(map);
|
|
|
|
if (rv != KERN_SUCCESS) {
|
|
vm_object_deallocate(object);
|
|
goto out;
|
|
}
|
|
tmap = vm_map_create(pmap_create(size), VM_MIN_ADDRESS,
|
|
VM_MIN_ADDRESS+size, TRUE);
|
|
off = VM_MIN_ADDRESS;
|
|
rv = vm_allocate_with_pager(tmap, &off, size,
|
|
FALSE, pager,
|
|
foff, FALSE);
|
|
if (rv != KERN_SUCCESS) {
|
|
vm_object_deallocate(object);
|
|
vm_map_deallocate(tmap);
|
|
goto out;
|
|
}
|
|
/*
|
|
* (XXX)
|
|
* MAP_PRIVATE implies that we see changes made by
|
|
* others. To ensure that we need to guarentee that
|
|
* no copy object is created (otherwise original
|
|
* pages would be pushed to the copy object and we
|
|
* would never see changes made by others). We
|
|
* totally sleeze it right now by marking the object
|
|
* internal temporarily.
|
|
*/
|
|
if ((flags & MAP_COPY) == 0)
|
|
object->flags |= OBJ_INTERNAL;
|
|
rv = vm_map_copy(map, tmap, *addr, size, off,
|
|
FALSE, FALSE);
|
|
object->flags &= ~OBJ_INTERNAL;
|
|
/*
|
|
* (XXX)
|
|
* My oh my, this only gets worse...
|
|
* Force creation of a shadow object so that
|
|
* vm_map_fork will do the right thing.
|
|
*/
|
|
if ((flags & MAP_COPY) == 0) {
|
|
vm_map_t tmap;
|
|
vm_map_entry_t tentry;
|
|
vm_object_t tobject;
|
|
vm_offset_t toffset;
|
|
vm_prot_t tprot;
|
|
boolean_t twired, tsu;
|
|
|
|
tmap = map;
|
|
vm_map_lookup(&tmap, *addr, VM_PROT_WRITE,
|
|
&tentry, &tobject, &toffset,
|
|
&tprot, &twired, &tsu);
|
|
vm_map_lookup_done(tmap, tentry);
|
|
}
|
|
/*
|
|
* (XXX)
|
|
* Map copy code cannot detect sharing unless a
|
|
* sharing map is involved. So we cheat and write
|
|
* protect everything ourselves.
|
|
*/
|
|
vm_object_pmap_copy(object, foff, foff + size);
|
|
vm_object_deallocate(object);
|
|
vm_map_deallocate(tmap);
|
|
if (rv != KERN_SUCCESS)
|
|
goto out;
|
|
}
|
|
#ifdef DEBUG
|
|
if (mmapdebug & MDB_MAPIT)
|
|
printf("vm_mmap(%d): FILE *addr %lx size %lx pager %p\n",
|
|
curproc->p_pid, *addr, size, pager);
|
|
#endif
|
|
}
|
|
/*
|
|
* 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_deallocate(map, *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_deallocate(map, *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);
|
|
}
|
|
}
|