/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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. 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 $Hdr: vm_unix.c 1.1 89/11/07$
*
* @(#)vm_unix.c 8.1 (Berkeley) 6/11/93
*/
/*
* Traditional sbrk/grow interface to VM
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/racct.h>
#include <sys/resourcevar.h>
#include <sys/syscallsubr.h>
#include <sys/sysent.h>
#include <sys/sysproto.h>
#include <sys/systm.h>
#if defined(__amd64__) || defined(__i386__) /* for i386_read_exec */
#include <machine/md_var.h>
#endif
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#ifndef _SYS_SYSPROTO_H_
struct break_args {
char *nsize;
};
#endif
int
sys_break(struct thread *td, struct break_args *uap)
{
#if !defined(__aarch64__) && !defined(__riscv)
uintptr_t addr;
int error;
addr = (uintptr_t)uap->nsize;
error = kern_break(td, &addr);
if (error == 0)
td->td_retval[0] = addr;
return (error);
#else /* defined(__aarch64__) || defined(__riscv) */
return (ENOSYS);
#endif /* defined(__aarch64__) || defined(__riscv) */
}
int
kern_break(struct thread *td, uintptr_t *addr)
{
struct vmspace *vm = td->td_proc->p_vmspace;
vm_map_t map = &vm->vm_map;
vm_offset_t new, old, base;
rlim_t datalim, lmemlim, vmemlim;
int prot, rv;
int error = 0;
datalim = lim_cur(td, RLIMIT_DATA);
lmemlim = lim_cur(td, RLIMIT_MEMLOCK);
vmemlim = lim_cur(td, RLIMIT_VMEM);
new = round_page(*addr);
vm_map_lock(map);
base = round_page((vm_offset_t) vm->vm_daddr);
old = base + ctob(vm->vm_dsize);
if (new > base) {
/*
* Check the resource limit, but allow a process to reduce
* its usage, even if it remains over the limit.
*/
if (new - base > datalim && new > old) {
error = ENOMEM;
goto done;
}
if (new > vm_map_max(map)) {
error = ENOMEM;
goto done;
}
} else if (new < base) {
/*
* Simply return the current break address without
* modifying any state. This is an ad-hoc interface
* used by libc to determine the initial break address,
* avoiding a dependency on magic features in the system
* linker.
*/
new = old;
goto done;
}
if (new > old) {
if (!old_mlock && map->flags & MAP_WIREFUTURE) {
if (ptoa(pmap_wired_count(map->pmap)) +
(new - old) > lmemlim) {
error = ENOMEM;
goto done;
}
}
if (map->size + (new - old) > vmemlim) {
error = ENOMEM;
goto done;
}
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(td->td_proc);
error = racct_set(td->td_proc, RACCT_DATA, new - base);
if (error != 0) {
PROC_UNLOCK(td->td_proc);
error = ENOMEM;
goto done;
}
error = racct_set(td->td_proc, RACCT_VMEM,
map->size + (new - old));
if (error != 0) {
racct_set_force(td->td_proc, RACCT_DATA,
old - base);
PROC_UNLOCK(td->td_proc);
error = ENOMEM;
goto done;
}
if (!old_mlock && map->flags & MAP_WIREFUTURE) {
error = racct_set(td->td_proc, RACCT_MEMLOCK,
ptoa(pmap_wired_count(map->pmap)) +
(new - old));
if (error != 0) {
racct_set_force(td->td_proc, RACCT_DATA,
old - base);
racct_set_force(td->td_proc, RACCT_VMEM,
map->size);
PROC_UNLOCK(td->td_proc);
error = ENOMEM;
goto done;
}
}
PROC_UNLOCK(td->td_proc);
}
#endif
prot = VM_PROT_RW;
#if (defined(COMPAT_FREEBSD32) && defined(__amd64__)) || defined(__i386__)
if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32))
prot |= VM_PROT_EXECUTE;
#endif
rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL,
0);
if (rv == KERN_SUCCESS && (map->flags & MAP_WIREFUTURE) != 0) {
rv = vm_map_wire_locked(map, old, new,
VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES);
if (rv != KERN_SUCCESS)
(void)vm_map_delete(map, old, new);
}
if (rv != KERN_SUCCESS) {
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(td->td_proc);
racct_set_force(td->td_proc,
RACCT_DATA, old - base);
racct_set_force(td->td_proc,
RACCT_VMEM, map->size);
if (!old_mlock && map->flags & MAP_WIREFUTURE) {
racct_set_force(td->td_proc,
RACCT_MEMLOCK,
ptoa(pmap_wired_count(map->pmap)));
}
PROC_UNLOCK(td->td_proc);
}
#endif
error = ENOMEM;
goto done;
}
vm->vm_dsize += btoc(new - old);
} else if (new < old) {
rv = vm_map_delete(map, new, old);
if (rv != KERN_SUCCESS) {
error = ENOMEM;
goto done;
}
vm->vm_dsize -= btoc(old - new);
#ifdef RACCT
if (racct_enable) {
PROC_LOCK(td->td_proc);
racct_set_force(td->td_proc, RACCT_DATA, new - base);
racct_set_force(td->td_proc, RACCT_VMEM, map->size);
if (!old_mlock && map->flags & MAP_WIREFUTURE) {
racct_set_force(td->td_proc, RACCT_MEMLOCK,
ptoa(pmap_wired_count(map->pmap)));
}
PROC_UNLOCK(td->td_proc);
}
#endif
}
done:
vm_map_unlock(map);
if (error == 0)
*addr = new;
return (error);
}
#ifdef COMPAT_FREEBSD11
int
freebsd11_vadvise(struct thread *td, struct freebsd11_vadvise_args *uap)
{
return (EINVAL);
}
#endif
