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freebsd/sys/vm/vm_mmap.c
Alfred Perlstein 2395531439 Introduce a global lock for the vm subsystem (vm_mtx).
vm_mtx does not recurse and is required for most low level
vm operations.

faults can not be taken without holding Giant.

Memory subsystems can now call the base page allocators safely.

Almost all atomic ops were removed as they are covered under the
vm mutex.

Alpha and ia64 now need to catch up to i386's trap handlers.

FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).

Reviewed (partially) by: jake, jhb
2001-05-19 01:28:09 +00:00

1233 lines
28 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
* $FreeBSD$
*/
/*
* Mapped file (mmap) interface to VM
*/
#include "opt_compat.h"
#include "opt_rlimit.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/filedesc.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/mman.h>
#include <sys/conf.h>
#include <sys/stat.h>
#include <sys/vmmeter.h>
#include <sys/sysctl.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/vm_pageout.h>
#include <vm/vm_extern.h>
#include <vm/vm_page.h>
#include <vm/vm_kern.h>
#ifndef _SYS_SYSPROTO_H_
struct sbrk_args {
int incr;
};
#endif
static int max_proc_mmap;
SYSCTL_INT(_vm, OID_AUTO, max_proc_mmap, CTLFLAG_RW, &max_proc_mmap, 0, "");
/*
* Set the maximum number of vm_map_entry structures per process. Roughly
* speaking vm_map_entry structures are tiny, so allowing them to eat 1/100
* of our KVM malloc space still results in generous limits. We want a
* default that is good enough to prevent the kernel running out of resources
* if attacked from compromised user account but generous enough such that
* multi-threaded processes are not unduly inconvenienced.
*/
static void vmmapentry_rsrc_init __P((void *));
SYSINIT(vmmersrc, SI_SUB_KVM_RSRC, SI_ORDER_FIRST, vmmapentry_rsrc_init, NULL)
static void
vmmapentry_rsrc_init(dummy)
void *dummy;
{
max_proc_mmap = vm_kmem_size / sizeof(struct vm_map_entry);
max_proc_mmap /= 100;
}
/* ARGSUSED */
int
sbrk(p, uap)
struct proc *p;
struct sbrk_args *uap;
{
/* Not yet implemented */
return (EOPNOTSUPP);
}
#ifndef _SYS_SYSPROTO_H_
struct sstk_args {
int incr;
};
#endif
/* ARGSUSED */
int
sstk(p, uap)
struct proc *p;
struct sstk_args *uap;
{
/* 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)
struct proc *p;
struct getpagesize_args *uap;
{
p->p_retval[0] = PAGE_SIZE;
return (0);
}
#endif /* COMPAT_43 || COMPAT_SUNOS */
/*
* Memory Map (mmap) system call. Note that the file offset
* and address are allowed to be NOT page aligned, though if
* the MAP_FIXED flag it set, both must have the same remainder
* modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not
* page-aligned, the actual mapping starts at trunc_page(addr)
* and the return value is adjusted up by the page offset.
*
* Generally speaking, only character devices which are themselves
* memory-based, such as a video framebuffer, can be mmap'd. Otherwise
* there would be no cache coherency between a descriptor and a VM mapping
* both to the same character device.
*
* Block devices can be mmap'd no matter what they represent. Cache coherency
* is maintained as long as you do not write directly to the underlying
* character device.
*/
#ifndef _SYS_SYSPROTO_H_
struct mmap_args {
void *addr;
size_t len;
int prot;
int flags;
int fd;
long pad;
off_t pos;
};
#endif
int
mmap(p, uap)
struct proc *p;
register struct mmap_args *uap;
{
register struct filedesc *fdp = p->p_fd;
register struct file *fp = NULL;
struct vnode *vp;
vm_offset_t addr;
vm_size_t size, pageoff;
vm_prot_t prot, maxprot;
void *handle;
int flags, error;
int disablexworkaround;
off_t pos;
struct vmspace *vms = p->p_vmspace;
vm_object_t obj;
addr = (vm_offset_t) uap->addr;
size = uap->len;
prot = uap->prot & VM_PROT_ALL;
flags = uap->flags;
pos = uap->pos;
/* make sure mapping fits into numeric range etc */
if ((ssize_t) uap->len < 0 ||
((flags & MAP_ANON) && uap->fd != -1))
return (EINVAL);
if (flags & MAP_STACK) {
if ((uap->fd != -1) ||
((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE)))
return (EINVAL);
flags |= MAP_ANON;
pos = 0;
}
/*
* Align the file position to a page boundary,
* and save its page offset component.
*/
pageoff = (pos & PAGE_MASK);
pos -= pageoff;
/* Adjust size for rounding (on both ends). */
size += pageoff; /* low end... */
size = (vm_size_t) round_page(size); /* hi end */
/*
* Check for illegal addresses. Watch out for address wrap... Note
* that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (flags & MAP_FIXED) {
/*
* The specified address must have the same remainder
* as the file offset taken modulo PAGE_SIZE, so it
* should be aligned after adjustment by pageoff.
*/
addr -= pageoff;
if (addr & PAGE_MASK)
return (EINVAL);
/* Address range must be all in user VM space. */
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 for non-fixed mappings where no hint is provided or
* the hint would fall in the potential heap space,
* place it after the end of the largest possible heap.
*
* There should really be a pmap call to determine a reasonable
* location.
*/
else if (addr == 0 ||
(addr >= round_page((vm_offset_t)vms->vm_taddr) &&
addr < round_page((vm_offset_t)vms->vm_daddr + MAXDSIZ)))
addr = round_page((vm_offset_t)vms->vm_daddr + MAXDSIZ);
if (flags & MAP_ANON) {
/*
* Mapping blank space is trivial.
*/
handle = NULL;
maxprot = VM_PROT_ALL;
pos = 0;
} 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);
/*
* don't let the descriptor disappear on us if we block
*/
fhold(fp);
/*
* POSIX shared-memory objects are defined to have
* kernel persistence, and are not defined to support
* read(2)/write(2) -- or even open(2). Thus, we can
* use MAP_ASYNC to trade on-disk coherence for speed.
* The shm_open(3) library routine turns on the FPOSIXSHM
* flag to request this behavior.
*/
if (fp->f_flag & FPOSIXSHM)
flags |= MAP_NOSYNC;
vp = (struct vnode *) fp->f_data;
if (vp->v_type != VREG && vp->v_type != VCHR)
return (EINVAL);
if (vp->v_type == VREG) {
/*
* Get the proper underlying object
*/
if (VOP_GETVOBJECT(vp, &obj) != 0)
return (EINVAL);
vp = (struct vnode*)obj->handle;
}
/*
* XXX hack to handle use of /dev/zero to map anon memory (ala
* SunOS).
*/
if ((vp->v_type == VCHR) &&
(vp->v_rdev->si_devsw->d_flags & D_MMAP_ANON)) {
handle = NULL;
maxprot = VM_PROT_ALL;
flags |= MAP_ANON;
pos = 0;
} else {
/*
* cdevs does not provide private mappings of any kind.
*/
/*
* However, for XIG X server to continue to work,
* we should allow the superuser to do it anyway.
* We only allow it at securelevel < 1.
* (Because the XIG X server writes directly to video
* memory via /dev/mem, it should never work at any
* other securelevel.
* XXX this will have to go
*/
if (securelevel >= 1)
disablexworkaround = 1;
else
disablexworkaround = suser(p);
if (vp->v_type == VCHR && disablexworkaround &&
(flags & (MAP_PRIVATE|MAP_COPY))) {
error = EINVAL;
goto done;
}
/*
* 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) {
error = EACCES;
goto done;
}
/*
* If we are sharing potential changes (either via
* MAP_SHARED or via the implicit sharing of character
* device mappings), and we are trying to get write
* permission although we opened it without asking
* for it, bail out. Check for superuser, only if
* we're at securelevel < 1, to allow the XIG X server
* to continue to work.
*/
if ((flags & MAP_SHARED) != 0 ||
(vp->v_type == VCHR && disablexworkaround)) {
if ((fp->f_flag & FWRITE) != 0) {
struct vattr va;
if ((error =
VOP_GETATTR(vp, &va,
p->p_ucred, p))) {
goto done;
}
if ((va.va_flags &
(SF_SNAPSHOT|IMMUTABLE|APPEND)) == 0) {
maxprot |= VM_PROT_WRITE;
} else if (prot & PROT_WRITE) {
error = EPERM;
goto done;
}
} else if ((prot & PROT_WRITE) != 0) {
error = EACCES;
goto done;
}
} else {
maxprot |= VM_PROT_WRITE;
}
handle = (void *)vp;
}
}
/*
* Do not allow more then a certain number of vm_map_entry structures
* per process. Scale with the number of rforks sharing the map
* to make the limit reasonable for threads.
*/
if (max_proc_mmap &&
vms->vm_map.nentries >= max_proc_mmap * vms->vm_refcnt) {
error = ENOMEM;
goto done;
}
error = vm_mmap(&vms->vm_map, &addr, size, prot, maxprot,
flags, handle, pos);
if (error == 0)
p->p_retval[0] = (register_t) (addr + pageoff);
done:
if (fp)
fdrop(fp, p);
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)
struct proc *p;
register struct ommap_args *uap;
{
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));
}
#endif /* COMPAT_43 */
#ifndef _SYS_SYSPROTO_H_
struct msync_args {
void *addr;
int len;
int flags;
};
#endif
int
msync(p, uap)
struct proc *p;
struct msync_args *uap;
{
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.
*/
mtx_lock(&vm_mtx);
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) {
mtx_unlock(&vm_mtx);
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);
mtx_unlock(&vm_mtx);
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 {
void *addr;
size_t len;
};
#endif
int
munmap(p, uap)
register struct proc *p;
register struct munmap_args *uap;
{
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
map = &p->p_vmspace->vm_map;
/*
* Make sure entire range is allocated.
*/
mtx_lock(&vm_mtx);
if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE)) {
mtx_unlock(&vm_mtx);
return (EINVAL);
}
/* returns nothing but KERN_SUCCESS anyway */
(void) vm_map_remove(map, addr, addr + size);
mtx_unlock(&vm_mtx);
return (0);
}
#if 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;
}
#endif
#ifndef _SYS_SYSPROTO_H_
struct mprotect_args {
const void *addr;
size_t len;
int prot;
};
#endif
int
mprotect(p, uap)
struct proc *p;
struct mprotect_args *uap;
{
vm_offset_t addr;
vm_size_t size, pageoff;
register vm_prot_t prot;
int ret;
addr = (vm_offset_t) uap->addr;
size = uap->len;
prot = uap->prot & VM_PROT_ALL;
#if defined(VM_PROT_READ_IS_EXEC)
if (prot & VM_PROT_READ)
prot |= VM_PROT_EXECUTE;
#endif
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return(EINVAL);
mtx_lock(&vm_mtx);
ret = vm_map_protect(&p->p_vmspace->vm_map, addr,
addr + size, prot, FALSE);
mtx_unlock(&vm_mtx);
switch (ret) {
case KERN_SUCCESS:
return (0);
case KERN_PROTECTION_FAILURE:
return (EACCES);
}
return (EINVAL);
}
#ifndef _SYS_SYSPROTO_H_
struct minherit_args {
void *addr;
size_t len;
int inherit;
};
#endif
int
minherit(p, uap)
struct proc *p;
struct minherit_args *uap;
{
vm_offset_t addr;
vm_size_t size, pageoff;
register vm_inherit_t inherit;
int ret;
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);
mtx_lock(&vm_mtx);
ret = vm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
inherit);
mtx_unlock(&vm_mtx);
switch (ret) {
case KERN_SUCCESS:
return (0);
case KERN_PROTECTION_FAILURE:
return (EACCES);
}
return (EINVAL);
}
#ifndef _SYS_SYSPROTO_H_
struct madvise_args {
void *addr;
size_t len;
int behav;
};
#endif
/* ARGSUSED */
int
madvise(p, uap)
struct proc *p;
struct madvise_args *uap;
{
vm_offset_t start, end;
int ret;
/*
* Check for illegal behavior
*/
if (uap->behav < 0 || uap->behav > MADV_CORE)
return (EINVAL);
/*
* 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);
mtx_lock(&vm_mtx);
ret = vm_map_madvise(&p->p_vmspace->vm_map, start, end, uap->behav);
mtx_unlock(&vm_mtx);
return (ret ? EINVAL : 0);
}
#ifndef _SYS_SYSPROTO_H_
struct mincore_args {
const void *addr;
size_t len;
char *vec;
};
#endif
/* ARGSUSED */
int
mincore(p, uap)
struct proc *p;
struct mincore_args *uap;
{
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;
unsigned int timestamp;
/*
* 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;
mtx_lock(&vm_mtx);
pmap = vmspace_pmap(p->p_vmspace);
vm_map_lock_read(map);
RestartScan:
timestamp = map->timestamp;
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->eflags & MAP_ENTRY_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(m))
mincoreinfo |= MINCORE_MODIFIED_OTHER;
if ((m->flags & PG_REFERENCED) ||
pmap_ts_referenced(m)) {
vm_page_flag_set(m, PG_REFERENCED);
mincoreinfo |= MINCORE_REFERENCED_OTHER;
}
}
}
/*
* subyte may page fault. In case it needs to modify
* the map, we release the lock.
*/
vm_map_unlock_read(map);
mtx_unlock(&vm_mtx);
/*
* 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) {
return (EFAULT);
}
++lastvecindex;
}
/*
* Pass the page information to the user
*/
error = subyte( vec + vecindex, mincoreinfo);
if (error) {
return (EFAULT);
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
mtx_lock(&vm_mtx);
vm_map_lock_read(map);
if (timestamp != map->timestamp)
goto RestartScan;
lastvecindex = vecindex;
addr += PAGE_SIZE;
}
}
/*
* subyte may page fault. In case it needs to modify
* the map, we release the lock.
*/
vm_map_unlock_read(map);
mtx_unlock(&vm_mtx);
/*
* 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) {
return (EFAULT);
}
++lastvecindex;
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
mtx_lock(&vm_mtx);
vm_map_lock_read(map);
if (timestamp != map->timestamp)
goto RestartScan;
vm_map_unlock_read(map);
mtx_unlock(&vm_mtx);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct mlock_args {
const void *addr;
size_t len;
};
#endif
int
mlock(p, uap)
struct proc *p;
struct mlock_args *uap;
{
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 (ENOMEM);
#else
error = suser(p);
if (error)
return (error);
#endif
mtx_lock(&vm_mtx);
error = vm_map_user_pageable(&p->p_vmspace->vm_map, addr,
addr + size, FALSE);
mtx_unlock(&vm_mtx);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
#ifndef _SYS_SYSPROTO_H_
struct mlockall_args {
int how;
};
#endif
int
mlockall(p, uap)
struct proc *p;
struct mlockall_args *uap;
{
return 0;
}
#ifndef _SYS_SYSPROTO_H_
struct mlockall_args {
int how;
};
#endif
int
munlockall(p, uap)
struct proc *p;
struct munlockall_args *uap;
{
return 0;
}
#ifndef _SYS_SYSPROTO_H_
struct munlock_args {
const void *addr;
size_t len;
};
#endif
int
munlock(p, uap)
struct proc *p;
struct munlock_args *uap;
{
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);
if (error)
return (error);
#endif
mtx_lock(&vm_mtx);
error = vm_map_user_pageable(&p->p_vmspace->vm_map, addr,
addr + size, TRUE);
mtx_lock(&vm_mtx);
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(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot,
vm_prot_t maxprot, int flags,
void *handle,
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;
mtx_lock(&vm_mtx);
(void) vm_map_remove(map, *addr, *addr + size);
mtx_unlock(&vm_mtx);
}
/*
* 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 = (void *)(intptr_t)vp->v_rdev;
} else {
struct vattr vat;
int error;
mtx_lock(&Giant);
error = VOP_GETATTR(vp, &vat, p->p_ucred, p);
mtx_unlock(&Giant);
if (error)
return (error);
objsize = round_page(vat.va_size);
type = OBJT_VNODE;
/*
* if it is a regular file without any references
* we do not need to sync it.
*/
if (vp->v_type == VREG && vat.va_nlink == 0) {
flags |= MAP_NOSYNC;
}
}
}
if (handle == NULL) {
object = NULL;
docow = 0;
} else {
object = vm_pager_allocate(type,
handle, objsize, prot, foff);
if (object == NULL)
return (type == OBJT_DEVICE ? EINVAL : ENOMEM);
docow = MAP_PREFAULT_PARTIAL;
}
/*
* Force device mappings to be shared.
*/
if (type == OBJT_DEVICE || type == OBJT_PHYS) {
flags &= ~(MAP_PRIVATE|MAP_COPY);
flags |= MAP_SHARED;
}
if ((flags & (MAP_ANON|MAP_SHARED)) == 0)
docow |= MAP_COPY_ON_WRITE;
if (flags & MAP_NOSYNC)
docow |= MAP_DISABLE_SYNCER;
if (flags & MAP_NOCORE)
docow |= MAP_DISABLE_COREDUMP;
#if defined(VM_PROT_READ_IS_EXEC)
if (prot & VM_PROT_READ)
prot |= VM_PROT_EXECUTE;
if (maxprot & VM_PROT_READ)
maxprot |= VM_PROT_EXECUTE;
#endif
mtx_lock(&vm_mtx);
if (fitit) {
*addr = pmap_addr_hint(object, *addr, size);
}
if (flags & MAP_STACK)
rv = vm_map_stack (map, *addr, size, prot,
maxprot, docow);
else
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;
}
/*
* 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:
mtx_unlock(&vm_mtx);
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);
}
}