FreeBSD-5.3/sys/vm/vm_mmap.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.
* 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
*/
/*
* Mapped file (mmap) interface to VM
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/vm/vm_mmap.c,v 1.192 2004/08/05 07:04:33 phk Exp $");
#include "opt_compat.h"
#include "opt_mac.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/resource.h>
#include <sys/resourcevar.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/mac.h>
#include <sys/mman.h>
#include <sys/mount.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(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;
}
static int vm_mmap_vnode(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *,
int *, struct vnode *, vm_ooffset_t, vm_object_t *);
/*
* MPSAFE
*/
/* ARGSUSED */
int
sbrk(td, uap)
struct thread *td;
struct sbrk_args *uap;
{
/* Not yet implemented */
/* mtx_lock(&Giant); */
/* mtx_unlock(&Giant); */
return (EOPNOTSUPP);
}
#ifndef _SYS_SYSPROTO_H_
struct sstk_args {
int incr;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
sstk(td, uap)
struct thread *td;
struct sstk_args *uap;
{
/* Not yet implemented */
/* mtx_lock(&Giant); */
/* mtx_unlock(&Giant); */
return (EOPNOTSUPP);
}
#if defined(COMPAT_43)
#ifndef _SYS_SYSPROTO_H_
struct getpagesize_args {
int dummy;
};
#endif
/* ARGSUSED */
int
ogetpagesize(td, uap)
struct thread *td;
struct getpagesize_args *uap;
{
/* MP SAFE */
td->td_retval[0] = PAGE_SIZE;
return (0);
}
#endif /* COMPAT_43 */
/*
* 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
/*
* MPSAFE
*/
int
mmap(td, uap)
struct thread *td;
struct mmap_args *uap;
{
struct file *fp;
struct vnode *vp;
vm_offset_t addr;
vm_size_t size, pageoff;
vm_prot_t prot, maxprot;
void *handle;
int flags, error;
off_t pos;
struct vmspace *vms = td->td_proc->p_vmspace;
addr = (vm_offset_t) uap->addr;
size = uap->len;
prot = uap->prot & VM_PROT_ALL;
flags = uap->flags;
pos = uap->pos;
fp = NULL;
/* 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 (addr < vm_map_min(&vms->vm_map) ||
addr + size > vm_map_max(&vms->vm_map))
return (EINVAL);
if (addr + size < addr)
return (EINVAL);
} else {
/*
* 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.
*/
PROC_LOCK(td->td_proc);
if (addr == 0 ||
(addr >= round_page((vm_offset_t)vms->vm_taddr) &&
addr < round_page((vm_offset_t)vms->vm_daddr +
lim_max(td->td_proc, RLIMIT_DATA))))
addr = round_page((vm_offset_t)vms->vm_daddr +
lim_max(td->td_proc, RLIMIT_DATA));
PROC_UNLOCK(td->td_proc);
}
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.
* don't let the descriptor disappear on us if we block
*/
if ((error = fget(td, uap->fd, &fp)) != 0)
goto done;
if (fp->f_type != DTYPE_VNODE) {
error = EINVAL;
goto done;
}
/*
* 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 = fp->f_vnode;
/*
* 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?
*/
if (vp->v_mount != NULL && vp->v_mount->mnt_flag & MNT_NOEXEC)
maxprot = VM_PROT_NONE;
else
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.
*/
if ((flags & MAP_SHARED) != 0) {
if ((fp->f_flag & FWRITE) != 0) {
maxprot |= VM_PROT_WRITE;
} else if ((prot & PROT_WRITE) != 0) {
error = EACCES;
goto done;
}
} else if (vp->v_type != VCHR || (fp->f_flag & FWRITE) != 0) {
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)
td->td_retval[0] = (register_t) (addr + pageoff);
done:
if (fp)
fdrop(fp, td);
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(td, uap)
struct thread *td;
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
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;
nargs.fd = uap->fd;
nargs.pos = uap->pos;
return (mmap(td, &nargs));
}
#endif /* COMPAT_43 */
#ifndef _SYS_SYSPROTO_H_
struct msync_args {
void *addr;
int len;
int flags;
};
#endif
/*
* MPSAFE
*/
int
msync(td, uap)
struct thread *td;
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 = &td->td_proc->p_vmspace->vm_map;
/*
* Clean the pages and interpret the return value.
*/
rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0,
(flags & MS_INVALIDATE) != 0);
switch (rv) {
case KERN_SUCCESS:
return (0);
case KERN_INVALID_ADDRESS:
return (EINVAL); /* Sun returns ENOMEM? */
case KERN_INVALID_ARGUMENT:
return (EBUSY);
default:
return (EINVAL);
}
}
#ifndef _SYS_SYSPROTO_H_
struct munmap_args {
void *addr;
size_t len;
};
#endif
/*
* MPSAFE
*/
int
munmap(td, uap)
struct thread *td;
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;
if (size == 0)
return (EINVAL);
pageoff = (addr & PAGE_MASK);
addr -= pageoff;
size += pageoff;
size = (vm_size_t) round_page(size);
if (addr + size < addr)
return (EINVAL);
/*
* Check for illegal addresses. Watch out for address wrap...
*/
map = &td->td_proc->p_vmspace->vm_map;
if (addr < vm_map_min(map) || addr + size > vm_map_max(map))
return (EINVAL);
vm_map_lock(map);
/*
* Make sure entire range is allocated.
*/
if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE)) {
vm_map_unlock(map);
return (EINVAL);
}
/* returns nothing but KERN_SUCCESS anyway */
vm_map_delete(map, addr, addr + size);
vm_map_unlock(map);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct mprotect_args {
const void *addr;
size_t len;
int prot;
};
#endif
/*
* MPSAFE
*/
int
mprotect(td, uap)
struct thread *td;
struct mprotect_args *uap;
{
vm_offset_t addr;
vm_size_t size, pageoff;
vm_prot_t prot;
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);
switch (vm_map_protect(&td->td_proc->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 {
void *addr;
size_t len;
int inherit;
};
#endif
/*
* MPSAFE
*/
int
minherit(td, uap)
struct thread *td;
struct minherit_args *uap;
{
vm_offset_t addr;
vm_size_t size, pageoff;
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(&td->td_proc->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 {
void *addr;
size_t len;
int behav;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
madvise(td, uap)
struct thread *td;
struct madvise_args *uap;
{
vm_offset_t start, end;
vm_map_t map;
struct proc *p;
int error;
/*
* Check for our special case, advising the swap pager we are
* "immortal."
*/
if (uap->behav == MADV_PROTECT) {
error = suser(td);
if (error == 0) {
p = td->td_proc;
PROC_LOCK(p);
p->p_flag |= P_PROTECTED;
PROC_UNLOCK(p);
}
return (error);
}
/*
* 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).
*/
map = &td->td_proc->p_vmspace->vm_map;
if ((vm_offset_t)uap->addr < vm_map_min(map) ||
(vm_offset_t)uap->addr + uap->len > vm_map_max(map))
return (EINVAL);
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);
if (vm_map_madvise(map, start, end, uap->behav))
return (EINVAL);
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct mincore_args {
const void *addr;
size_t len;
char *vec;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
mincore(td, uap)
struct thread *td;
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 = 0;
int vecindex, lastvecindex;
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);
map = &td->td_proc->p_vmspace->vm_map;
if (end > vm_map_max(map) || end < addr)
return (EINVAL);
/*
* Address of byte vector
*/
vec = uap->vec;
pmap = vmspace_pmap(td->td_proc->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);
VM_OBJECT_LOCK(current->object.vm_object);
m = vm_page_lookup(current->object.vm_object,
pindex);
/*
* if the page is resident, then gather information about
* it.
*/
if (m != NULL && m->valid != 0) {
mincoreinfo = MINCORE_INCORE;
vm_page_lock_queues();
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;
}
vm_page_unlock_queues();
}
VM_OBJECT_UNLOCK(current->object.vm_object);
}
/*
* subyte may page fault. In case it needs to modify
* the map, we release the lock.
*/
vm_map_unlock_read(map);
/*
* 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) {
error = EFAULT;
goto done2;
}
++lastvecindex;
}
/*
* Pass the page information to the user
*/
error = subyte(vec + vecindex, mincoreinfo);
if (error) {
error = EFAULT;
goto done2;
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
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);
/*
* 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) {
error = EFAULT;
goto done2;
}
++lastvecindex;
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
vm_map_lock_read(map);
if (timestamp != map->timestamp)
goto RestartScan;
vm_map_unlock_read(map);
done2:
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct mlock_args {
const void *addr;
size_t len;
};
#endif
/*
* MPSAFE
*/
int
mlock(td, uap)
struct thread *td;
struct mlock_args *uap;
{
struct proc *proc;
vm_offset_t addr, end, last, start;
vm_size_t npages, size;
int error;
error = suser(td);
if (error)
return (error);
addr = (vm_offset_t)uap->addr;
size = uap->len;
last = addr + size;
start = trunc_page(addr);
end = round_page(last);
if (last < addr || end < addr)
return (EINVAL);
npages = atop(end - start);
if (npages > vm_page_max_wired)
return (ENOMEM);
proc = td->td_proc;
PROC_LOCK(proc);
if (ptoa(npages +
pmap_wired_count(vm_map_pmap(&proc->p_vmspace->vm_map))) >
lim_cur(proc, RLIMIT_MEMLOCK)) {
PROC_UNLOCK(proc);
return (ENOMEM);
}
PROC_UNLOCK(proc);
if (npages + cnt.v_wire_count > vm_page_max_wired)
return (EAGAIN);
error = vm_map_wire(&proc->p_vmspace->vm_map, start, end,
VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
#ifndef _SYS_SYSPROTO_H_
struct mlockall_args {
int how;
};
#endif
/*
* MPSAFE
*/
int
mlockall(td, uap)
struct thread *td;
struct mlockall_args *uap;
{
vm_map_t map;
int error;
map = &td->td_proc->p_vmspace->vm_map;
error = 0;
if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0))
return (EINVAL);
#if 0
/*
* If wiring all pages in the process would cause it to exceed
* a hard resource limit, return ENOMEM.
*/
PROC_LOCK(td->td_proc);
if (map->size - ptoa(pmap_wired_count(vm_map_pmap(map)) >
lim_cur(td->td_proc, RLIMIT_MEMLOCK))) {
PROC_UNLOCK(td->td_proc);
return (ENOMEM);
}
PROC_UNLOCK(td->td_proc);
#else
error = suser(td);
if (error)
return (error);
#endif
if (uap->how & MCL_FUTURE) {
vm_map_lock(map);
vm_map_modflags(map, MAP_WIREFUTURE, 0);
vm_map_unlock(map);
error = 0;
}
if (uap->how & MCL_CURRENT) {
/*
* P1003.1-2001 mandates that all currently mapped pages
* will be memory resident and locked (wired) upon return
* from mlockall(). vm_map_wire() will wire pages, by
* calling vm_fault_wire() for each page in the region.
*/
error = vm_map_wire(map, vm_map_min(map), vm_map_max(map),
VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK);
error = (error == KERN_SUCCESS ? 0 : EAGAIN);
}
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct munlockall_args {
register_t dummy;
};
#endif
/*
* MPSAFE
*/
int
munlockall(td, uap)
struct thread *td;
struct munlockall_args *uap;
{
vm_map_t map;
int error;
map = &td->td_proc->p_vmspace->vm_map;
error = suser(td);
if (error)
return (error);
/* Clear the MAP_WIREFUTURE flag from this vm_map. */
vm_map_lock(map);
vm_map_modflags(map, 0, MAP_WIREFUTURE);
vm_map_unlock(map);
/* Forcibly unwire all pages. */
error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map),
VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct munlock_args {
const void *addr;
size_t len;
};
#endif
/*
* MPSAFE
*/
int
munlock(td, uap)
struct thread *td;
struct munlock_args *uap;
{
vm_offset_t addr, end, last, start;
vm_size_t size;
int error;
error = suser(td);
if (error)
return (error);
addr = (vm_offset_t)uap->addr;
size = uap->len;
last = addr + size;
start = trunc_page(addr);
end = round_page(last);
if (last < addr || end < addr)
return (EINVAL);
error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end,
VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES);
return (error == KERN_SUCCESS ? 0 : ENOMEM);
}
/*
* vm_mmap_vnode()
*
* MPSAFE
*
* Helper function for vm_mmap. Perform sanity check specific for mmap
* operations on vnodes.
*/
int
vm_mmap_vnode(struct thread *td, vm_size_t objsize,
vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp,
struct vnode *vp, vm_ooffset_t foff, vm_object_t *objp)
{
struct vattr va;
void *handle;
vm_object_t obj;
int error, flags, type;
mtx_lock(&Giant);
if ((error = vget(vp, LK_EXCLUSIVE, td)) != 0) {
mtx_unlock(&Giant);
return (error);
}
flags = *flagsp;
if (vp->v_type == VREG) {
/*
* Get the proper underlying object
*/
if (VOP_GETVOBJECT(vp, &obj) != 0) {
error = EINVAL;
goto done;
}
if (obj->handle != vp) {
vput(vp);
vp = (struct vnode*)obj->handle;
vget(vp, LK_EXCLUSIVE, td);
}
type = OBJT_VNODE;
handle = vp;
} else if (vp->v_type == VCHR) {
type = OBJT_DEVICE;
handle = vp->v_rdev;
if(vp->v_rdev->si_devsw->d_flags & D_MMAP_ANON) {
*maxprotp = VM_PROT_ALL;
*flagsp |= MAP_ANON;
error = 0;
goto done;
}
/*
* cdevs does not provide private mappings of any kind.
*/
if ((*maxprotp & VM_PROT_WRITE) == 0 &&
(prot & PROT_WRITE) != 0) {
error = EACCES;
goto done;
}
if (flags & (MAP_PRIVATE|MAP_COPY)) {
error = EINVAL;
goto done;
}
/*
* Force device mappings to be shared.
*/
flags &= ~(MAP_PRIVATE|MAP_COPY);
flags |= MAP_SHARED;
} else {
error = EINVAL;
goto done;
}
if ((error = VOP_GETATTR(vp, &va, td->td_ucred, td))) {
goto done;
}
if ((flags & MAP_SHARED) != 0) {
if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) {
if (prot & PROT_WRITE) {
error = EPERM;
goto done;
}
*maxprotp &= ~VM_PROT_WRITE;
}
#ifdef MAC
error = mac_check_vnode_mmap(td->td_ucred, vp, prot);
if (error != 0)
goto done;
#endif
}
/*
* If it is a regular file without any references
* we do not need to sync it.
* Adjust object size to be the size of actual file.
*/
if (vp->v_type == VREG) {
objsize = round_page(va.va_size);
if (va.va_nlink == 0)
flags |= MAP_NOSYNC;
}
obj = vm_pager_allocate(type, handle, objsize, prot, foff);
if (obj == NULL) {
error = (type == OBJT_DEVICE ? EINVAL : ENOMEM);
goto done;
}
*objp = obj;
*flagsp = flags;
done:
vput(vp);
mtx_unlock(&Giant);
return (error);
}
/*
* vm_mmap()
*
* MPSAFE
*
* 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;
int rv = KERN_SUCCESS;
vm_ooffset_t objsize;
int docow, error;
struct thread *td = curthread;
if (size == 0)
return (0);
objsize = size = round_page(size);
PROC_LOCK(td->td_proc);
if (td->td_proc->p_vmspace->vm_map.size + size >
lim_cur(td->td_proc, RLIMIT_VMEM)) {
PROC_UNLOCK(td->td_proc);
return(ENOMEM);
}
PROC_UNLOCK(td->td_proc);
/*
* 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 (handle != NULL) {
error = vm_mmap_vnode(td, size, prot, &maxprot, &flags,
handle, foff, &object);
if (error) {
return (error);
}
}
if (flags & MAP_ANON) {
object = NULL;
docow = 0;
/*
* Unnamed anonymous regions always start at 0.
*/
if (handle == 0)
foff = 0;
} else {
docow = MAP_PREFAULT_PARTIAL;
}
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
if (fitit)
*addr = pmap_addr_hint(object, *addr, size);
if (flags & MAP_STACK)
rv = vm_map_stack(map, *addr, size, prot, maxprot,
docow | MAP_STACK_GROWS_DOWN);
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);
} else if (flags & MAP_SHARED) {
/*
* Shared memory is also shared with children.
*/
rv = vm_map_inherit(map, *addr, *addr + size, VM_INHERIT_SHARE);
if (rv != KERN_SUCCESS)
(void) vm_map_remove(map, *addr, *addr + size);
}
/*
* If the process has requested that all future mappings
* be wired, then heed this.
*/
if ((rv == KERN_SUCCESS) && (map->flags & MAP_WIREFUTURE))
vm_map_wire(map, *addr, *addr + size,
VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
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);
}
}