freebsd-dev/sys/vm/vm_mmap.c
John Dyson 7aaaa4fd5d Implement closer-to POSIX mlock semantics. The major difference is
that we do allow mlock to span unallocated regions (of course, not
mlocking them.)  We also allow mlocking of RO regions (which the old
code couldn't.)  The restriction there is that once a RO region is
wired (mlocked), it cannot be debugged (or EVER written to.)

Under normal usage, the new mlock code will be a significant improvement
over our old stuff.
1996-12-14 17:54:17 +00:00

968 lines
21 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
*
* @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94
* $Id: vm_mmap.c,v 1.53 1996/10/29 22:07:11 dyson Exp $
*/
/*
* Mapped file (mmap) interface to VM
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/filedesc.h>
#include <sys/resourcevar.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/conf.h>
#include <sys/vmmeter.h>
#include <miscfs/specfs/specdev.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_prot.h>
#include <vm/vm_inherit.h>
#include <vm/lock.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_pager.h>
#include <vm/vm_pageout.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#ifndef _SYS_SYSPROTO_H_
struct sbrk_args {
int incr;
};
#endif
/* ARGSUSED */
int
sbrk(p, uap, retval)
struct proc *p;
struct sbrk_args *uap;
int *retval;
{
/* Not yet implemented */
return (EOPNOTSUPP);
}
#ifndef _SYS_SYSPROTO_H_
struct sstk_args {
int incr;
};
#endif
/* ARGSUSED */
int
sstk(p, uap, retval)
struct proc *p;
struct sstk_args *uap;
int *retval;
{
/* Not yet implemented */
return (EOPNOTSUPP);
}
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
#ifndef _SYS_SYSPROTO_H_
struct getpagesize_args {
int dummy;
};
#endif
/* ARGSUSED */
int
ogetpagesize(p, uap, retval)
struct proc *p;
struct getpagesize_args *uap;
int *retval;
{
*retval = PAGE_SIZE;
return (0);
}
#endif /* COMPAT_43 || COMPAT_SUNOS */
#ifndef _SYS_SYSPROTO_H_
struct mmap_args {
caddr_t addr;
size_t len;
int prot;
int flags;
int fd;
long pad;
off_t pos;
};
#endif
int
mmap(p, uap, retval)
struct proc *p;
register struct mmap_args *uap;
int *retval;
{
register struct filedesc *fdp = p->p_fd;
register struct file *fp;
struct vnode *vp;
vm_offset_t addr;
vm_size_t size, pageoff;
vm_prot_t prot, maxprot;
caddr_t handle;
int flags, error;
prot = uap->prot & VM_PROT_ALL;
flags = uap->flags;
/*
* Address (if FIXED) must be page aligned. Size is implicitly rounded
* to a page boundary.
*/
addr = (vm_offset_t) uap->addr;
if (((flags & MAP_FIXED) && (addr & PAGE_MASK)) ||
(ssize_t) uap->len < 0 || ((flags & MAP_ANON) && uap->fd != -1))
return (EINVAL);
/*
* Round page if not already disallowed by above test
* XXX: Is there any point in the MAP_FIXED align requirement above?
*/
size = uap->len;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
/*
* Check for illegal addresses. Watch out for address wrap... Note
* that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (flags & MAP_FIXED) {
if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
return (EINVAL);
#ifndef i386
if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
return (EINVAL);
#endif
if (addr + size < addr)
return (EINVAL);
}
/*
* XXX if no hint provided for a non-fixed mapping place it after the
* end of the largest possible heap.
*
* There should really be a pmap call to determine a reasonable location.
*/
if (addr == 0 && (flags & MAP_FIXED) == 0)
addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
if (flags & MAP_ANON) {
/*
* Mapping blank space is trivial.
*/
handle = NULL;
maxprot = VM_PROT_ALL;
} else {
/*
* Mapping file, get fp for validation. Obtain vnode and make
* sure it is of appropriate type.
*/
if (((unsigned) uap->fd) >= fdp->fd_nfiles ||
(fp = fdp->fd_ofiles[uap->fd]) == NULL)
return (EBADF);
if (fp->f_type != DTYPE_VNODE)
return (EINVAL);
vp = (struct vnode *) fp->f_data;
if (vp->v_type != VREG && vp->v_type != VCHR)
return (EINVAL);
/*
* XXX hack to handle use of /dev/zero to map anon memory (ala
* SunOS).
*/
if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
handle = NULL;
maxprot = VM_PROT_ALL;
flags |= MAP_ANON;
} else {
/*
* Ensure that file and memory protections are
* compatible. Note that we only worry about
* writability if mapping is shared; in this case,
* current and max prot are dictated by the open file.
* XXX use the vnode instead? Problem is: what
* credentials do we use for determination? What if
* proc does a setuid?
*/
maxprot = VM_PROT_EXECUTE; /* ??? */
if (fp->f_flag & FREAD)
maxprot |= VM_PROT_READ;
else if (prot & PROT_READ)
return (EACCES);
if (flags & MAP_SHARED) {
if (fp->f_flag & FWRITE)
maxprot |= VM_PROT_WRITE;
else if (prot & PROT_WRITE)
return (EACCES);
} else
maxprot |= VM_PROT_WRITE;
handle = (caddr_t) vp;
}
}
error = vm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
flags, handle, uap->pos);
if (error == 0)
*retval = (int) addr;
return (error);
}
#ifdef COMPAT_43
#ifndef _SYS_SYSPROTO_H_
struct ommap_args {
caddr_t addr;
int len;
int prot;
int flags;
int fd;
long pos;
};
#endif
int
ommap(p, uap, retval)
struct proc *p;
register struct ommap_args *uap;
int *retval;
{
struct mmap_args nargs;
static const char cvtbsdprot[8] = {
0,
PROT_EXEC,
PROT_WRITE,
PROT_EXEC | PROT_WRITE,
PROT_READ,
PROT_EXEC | PROT_READ,
PROT_WRITE | PROT_READ,
PROT_EXEC | PROT_WRITE | PROT_READ,
};
#define OMAP_ANON 0x0002
#define OMAP_COPY 0x0020
#define OMAP_SHARED 0x0010
#define OMAP_FIXED 0x0100
#define OMAP_INHERIT 0x0800
nargs.addr = uap->addr;
nargs.len = uap->len;
nargs.prot = cvtbsdprot[uap->prot & 0x7];
nargs.flags = 0;
if (uap->flags & OMAP_ANON)
nargs.flags |= MAP_ANON;
if (uap->flags & OMAP_COPY)
nargs.flags |= MAP_COPY;
if (uap->flags & OMAP_SHARED)
nargs.flags |= MAP_SHARED;
else
nargs.flags |= MAP_PRIVATE;
if (uap->flags & OMAP_FIXED)
nargs.flags |= MAP_FIXED;
if (uap->flags & OMAP_INHERIT)
nargs.flags |= MAP_INHERIT;
nargs.fd = uap->fd;
nargs.pos = uap->pos;
return (mmap(p, &nargs, retval));
}
#endif /* COMPAT_43 */
#ifndef _SYS_SYSPROTO_H_
struct msync_args {
caddr_t addr;
int len;
int flags;
};
#endif
int
msync(p, uap, retval)
struct proc *p;
struct msync_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
int flags;
vm_map_t map;
int rv;
addr = (vm_offset_t) uap->addr;
size = uap->len;
flags = uap->flags;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return(EINVAL);
if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE))
return (EINVAL);
map = &p->p_vmspace->vm_map;
/*
* XXX Gak! If size is zero we are supposed to sync "all modified
* pages with the region containing addr". Unfortunately, we don't
* really keep track of individual mmaps so we approximate by flushing
* the range of the map entry containing addr. This can be incorrect
* if the region splits or is coalesced with a neighbor.
*/
if (size == 0) {
vm_map_entry_t entry;
vm_map_lock_read(map);
rv = vm_map_lookup_entry(map, addr, &entry);
vm_map_unlock_read(map);
if (rv == FALSE)
return (EINVAL);
addr = entry->start;
size = entry->end - entry->start;
}
/*
* Clean the pages and interpret the return value.
*/
rv = vm_map_clean(map, addr, addr + size, (flags & MS_ASYNC) == 0,
(flags & MS_INVALIDATE) != 0);
switch (rv) {
case KERN_SUCCESS:
break;
case KERN_INVALID_ADDRESS:
return (EINVAL); /* Sun returns ENOMEM? */
case KERN_FAILURE:
return (EIO);
default:
return (EINVAL);
}
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct munmap_args {
caddr_t addr;
size_t len;
};
#endif
int
munmap(p, uap, retval)
register struct proc *p;
register struct munmap_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
vm_map_t map;
addr = (vm_offset_t) uap->addr;
size = uap->len;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return(EINVAL);
if (size == 0)
return (0);
/*
* Check for illegal addresses. Watch out for address wrap... Note
* that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
return (EINVAL);
#ifndef i386
if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
return (EINVAL);
#endif
if (addr + size < addr)
return (EINVAL);
map = &p->p_vmspace->vm_map;
/*
* Make sure entire range is allocated.
*/
if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE))
return (EINVAL);
/* returns nothing but KERN_SUCCESS anyway */
(void) vm_map_remove(map, addr, addr + size);
return (0);
}
void
munmapfd(p, fd)
struct proc *p;
int fd;
{
/*
* XXX should unmap any regions mapped to this file
*/
p->p_fd->fd_ofileflags[fd] &= ~UF_MAPPED;
}
#ifndef _SYS_SYSPROTO_H_
struct mprotect_args {
caddr_t addr;
size_t len;
int prot;
};
#endif
int
mprotect(p, uap, retval)
struct proc *p;
struct mprotect_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
register vm_prot_t prot;
addr = (vm_offset_t) uap->addr;
size = uap->len;
prot = uap->prot & VM_PROT_ALL;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return(EINVAL);
switch (vm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot,
FALSE)) {
case KERN_SUCCESS:
return (0);
case KERN_PROTECTION_FAILURE:
return (EACCES);
}
return (EINVAL);
}
#ifndef _SYS_SYSPROTO_H_
struct minherit_args {
caddr_t addr;
size_t len;
int inherit;
};
#endif
int
minherit(p, uap, retval)
struct proc *p;
struct minherit_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
register vm_inherit_t inherit;
addr = (vm_offset_t)uap->addr;
size = uap->len;
inherit = uap->inherit;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return(EINVAL);
switch (vm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
inherit)) {
case KERN_SUCCESS:
return (0);
case KERN_PROTECTION_FAILURE:
return (EACCES);
}
return (EINVAL);
}
#ifndef _SYS_SYSPROTO_H_
struct madvise_args {
caddr_t addr;
size_t len;
int behav;
};
#endif
/* ARGSUSED */
int
madvise(p, uap, retval)
struct proc *p;
struct madvise_args *uap;
int *retval;
{
vm_map_t map;
pmap_t pmap;
vm_offset_t start, end;
/*
* Check for illegal addresses. Watch out for address wrap... Note
* that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (VM_MAXUSER_ADDRESS > 0 &&
((vm_offset_t) uap->addr + uap->len) > VM_MAXUSER_ADDRESS)
return (EINVAL);
#ifndef i386
if (VM_MIN_ADDRESS > 0 && uap->addr < VM_MIN_ADDRESS)
return (EINVAL);
#endif
if (((vm_offset_t) uap->addr + uap->len) < (vm_offset_t) uap->addr)
return (EINVAL);
/*
* Since this routine is only advisory, we default to conservative
* behavior.
*/
start = trunc_page((vm_offset_t) uap->addr);
end = round_page((vm_offset_t) uap->addr + uap->len);
map = &p->p_vmspace->vm_map;
pmap = &p->p_vmspace->vm_pmap;
vm_map_madvise(map, pmap, start, end, uap->behav);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct mincore_args {
caddr_t addr;
size_t len;
char *vec;
};
#endif
/* ARGSUSED */
int
mincore(p, uap, retval)
struct proc *p;
struct mincore_args *uap;
int *retval;
{
vm_offset_t addr, first_addr;
vm_offset_t end, cend;
pmap_t pmap;
vm_map_t map;
char *vec;
int error;
int vecindex, lastvecindex;
register vm_map_entry_t current;
vm_map_entry_t entry;
int mincoreinfo;
/*
* Make sure that the addresses presented are valid for user
* mode.
*/
first_addr = addr = trunc_page((vm_offset_t) uap->addr);
end = addr + (vm_size_t)round_page(uap->len);
if (VM_MAXUSER_ADDRESS > 0 && end > VM_MAXUSER_ADDRESS)
return (EINVAL);
if (end < addr)
return (EINVAL);
/*
* Address of byte vector
*/
vec = uap->vec;
map = &p->p_vmspace->vm_map;
pmap = &p->p_vmspace->vm_pmap;
vm_map_lock(map);
/*
* Not needed here
*/
#if 0
VM_MAP_RANGE_CHECK(map, addr, end);
#endif
if (!vm_map_lookup_entry(map, addr, &entry))
entry = entry->next;
/*
* Do this on a map entry basis so that if the pages are not
* in the current processes address space, we can easily look
* up the pages elsewhere.
*/
lastvecindex = -1;
for(current = entry;
(current != &map->header) && (current->start < end);
current = current->next) {
/*
* ignore submaps (for now) or null objects
*/
if (current->is_a_map || current->is_sub_map ||
current->object.vm_object == NULL)
continue;
/*
* limit this scan to the current map entry and the
* limits for the mincore call
*/
if (addr < current->start)
addr = current->start;
cend = current->end;
if (cend > end)
cend = end;
/*
* scan this entry one page at a time
*/
while(addr < cend) {
/*
* Check pmap first, it is likely faster, also
* it can provide info as to whether we are the
* one referencing or modifying the page.
*/
mincoreinfo = pmap_mincore(pmap, addr);
if (!mincoreinfo) {
vm_pindex_t pindex;
vm_ooffset_t offset;
vm_page_t m;
/*
* calculate the page index into the object
*/
offset = current->offset + (addr - current->start);
pindex = OFF_TO_IDX(offset);
m = vm_page_lookup(current->object.vm_object,
pindex);
/*
* if the page is resident, then gather information about
* it.
*/
if (m) {
mincoreinfo = MINCORE_INCORE;
if (m->dirty ||
pmap_is_modified(VM_PAGE_TO_PHYS(m)))
mincoreinfo |= MINCORE_MODIFIED_OTHER;
if ((m->flags & PG_REFERENCED) ||
pmap_is_referenced(VM_PAGE_TO_PHYS(m)))
mincoreinfo |= MINCORE_REFERENCED_OTHER;
}
}
/*
* calculate index into user supplied byte vector
*/
vecindex = OFF_TO_IDX(addr - first_addr);
/*
* If we have skipped map entries, we need to make sure that
* the byte vector is zeroed for those skipped entries.
*/
while((lastvecindex + 1) < vecindex) {
error = subyte( vec + lastvecindex, 0);
if (error) {
vm_map_unlock(map);
return (EFAULT);
}
++lastvecindex;
}
/*
* Pass the page information to the user
*/
error = subyte( vec + vecindex, mincoreinfo);
if (error) {
vm_map_unlock(map);
return (EFAULT);
}
lastvecindex = vecindex;
addr += PAGE_SIZE;
}
}
/*
* Zero the last entries in the byte vector.
*/
vecindex = OFF_TO_IDX(end - first_addr);
while((lastvecindex + 1) < vecindex) {
error = subyte( vec + lastvecindex, 0);
if (error) {
vm_map_unlock(map);
return (EFAULT);
}
++lastvecindex;
}
vm_map_unlock(map);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct mlock_args {
caddr_t addr;
size_t len;
};
#endif
int
mlock(p, uap, retval)
struct proc *p;
struct mlock_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
int error;
addr = (vm_offset_t) uap->addr;
size = uap->len;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
/* disable wrap around */
if (addr + 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
error = suser(p->p_ucred, &p->p_acflag);
if (error)
return (error);
#endif
error = vm_map_user_pageable(&p->p_vmspace->vm_map, addr, addr + size, FALSE);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
#ifndef _SYS_SYSPROTO_H_
struct munlock_args {
caddr_t addr;
size_t len;
};
#endif
int
munlock(p, uap, retval)
struct proc *p;
struct munlock_args *uap;
int *retval;
{
vm_offset_t addr;
vm_size_t size, pageoff;
int error;
addr = (vm_offset_t) uap->addr;
size = uap->len;
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
/* disable wrap around */
if (addr + size < addr)
return (EINVAL);
#ifndef pmap_wired_count
error = suser(p->p_ucred, &p->p_acflag);
if (error)
return (error);
#endif
error = vm_map_user_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_ooffset_t foff;
{
boolean_t fitit;
vm_object_t object;
struct vnode *vp = NULL;
objtype_t type;
int rv = KERN_SUCCESS;
vm_ooffset_t objsize;
int docow;
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 object.
*/
if (flags & MAP_ANON) {
type = OBJT_DEFAULT;
/*
* Unnamed anonymous regions always start at 0.
*/
if (handle == 0)
foff = 0;
} else {
vp = (struct vnode *) handle;
if (vp->v_type == VCHR) {
type = OBJT_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 = round_page(vat.va_size);
type = OBJT_VNODE;
}
}
object = vm_pager_allocate(type, handle, OFF_TO_IDX(objsize), prot, foff);
if (object == NULL)
return (type == OBJT_DEVICE ? EINVAL : ENOMEM);
/*
* Force device mappings to be shared.
*/
if (type == OBJT_DEVICE) {
flags &= ~(MAP_PRIVATE|MAP_COPY);
flags |= MAP_SHARED;
}
docow = 0;
if ((flags & (MAP_ANON|MAP_SHARED)) == 0) {
docow = MAP_COPY_ON_WRITE | MAP_COPY_NEEDED;
}
rv = vm_map_find(map, object, foff, addr, size, fitit,
prot, maxprot, docow);
if (rv != KERN_SUCCESS) {
/*
* Lose the object reference. Will destroy the
* object if it's an unnamed anonymous mapping
* or named anonymous without other references.
*/
vm_object_deallocate(object);
goto out;
}
/*
* "Pre-fault" resident pages.
*/
if ((type == OBJT_VNODE) && (map->pmap != NULL)) {
pmap_object_init_pt(map->pmap, *addr,
object, (vm_pindex_t) OFF_TO_IDX(foff), size, 1);
}
/*
* Shared memory is also shared with children.
*/
if (flags & (MAP_SHARED|MAP_INHERIT)) {
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:
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);
}
}