/* $NetBSD: uvm_unix.c,v 1.48 2017/05/06 21:34:52 joerg Exp $ */ /* * Copyright (c) 1997 Charles D. Cranor and Washington University. * Copyright (c) 1991, 1993 The Regents of the University of California. * Copyright (c) 1988 University of Utah. * * 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 * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp */ /* * uvm_unix.c: traditional sbrk/grow interface to vm. */ #include __KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.48 2017/05/06 21:34:52 joerg Exp $"); #include "opt_pax.h" #include #include #include #include #include #include #include #include /* * sys_obreak: set break */ int sys_obreak(struct lwp *l, const struct sys_obreak_args *uap, register_t *retval) { /* { syscallarg(char *) nsize; } */ struct proc *p = l->l_proc; struct vmspace *vm = p->p_vmspace; vaddr_t nbreak, obreak; int error; mutex_enter(&p->p_auxlock); obreak = (vaddr_t)vm->vm_daddr; nbreak = round_page((vaddr_t)SCARG(uap, nsize)); if (nbreak == 0 || ((nbreak - obreak) > p->p_rlimit[RLIMIT_DATA].rlim_cur && nbreak > obreak)) { mutex_exit(&p->p_auxlock); return (ENOMEM); } obreak = round_page(obreak + ptoa(vm->vm_dsize)); if (nbreak == obreak) { mutex_exit(&p->p_auxlock); return (0); } /* * grow or shrink? */ if (nbreak > obreak) { vm_prot_t prot = UVM_PROT_RW; vm_prot_t maxprot; maxprot = PAX_MPROTECT_MAXPROTECT(l, prot, 0, UVM_PROT_ALL); error = uvm_map(&vm->vm_map, &obreak, nbreak - obreak, NULL, UVM_UNKNOWN_OFFSET, 0, UVM_MAPFLAG(prot, maxprot, UVM_INH_COPY, UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); if (error) { #ifdef DEBUG uprintf("sbrk: grow %#"PRIxVADDR" failed, error = %d\n", nbreak - obreak, error); #endif mutex_exit(&p->p_auxlock); return (error); } vm->vm_dsize += atop(nbreak - obreak); } else { uvm_deallocate(&vm->vm_map, nbreak, obreak - nbreak); vm->vm_dsize -= atop(obreak - nbreak); } mutex_exit(&p->p_auxlock); return (0); } /* * uvm_grow: enlarge the "stack segment" to include sp. */ int uvm_grow(struct proc *p, vaddr_t sp) { struct vmspace *vm = p->p_vmspace; vsize_t nss; /* * For user defined stacks (from sendsig). */ #ifdef __MACHINE_STACK_GROWS_UP if (sp < (vaddr_t)vm->vm_minsaddr) #else if (sp < (vaddr_t)vm->vm_maxsaddr) #endif return (0); /* * For common case of already allocated (from trap). */ #ifdef __MACHINE_STACK_GROWS_UP if (sp < USRSTACK + ctob(vm->vm_ssize)) #else if (sp >= USRSTACK - ctob(vm->vm_ssize)) #endif return (1); /* * Really need to check vs limit and increment stack size if ok. */ #ifdef __MACHINE_STACK_GROWS_UP nss = btoc(sp - USRSTACK); #else nss = btoc(USRSTACK - sp); #endif if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) return (0); vm->vm_ssize = nss; return (1); } /* * sys_oadvise: old advice system call */ /* ARGSUSED */ int sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval) { #if 0 /* { syscallarg(int) anom; } */ #endif return (EINVAL); }