1 /* $NetBSD: uvm_unix.c,v 1.43 2009/12/15 06:15:11 matt Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Charles D. Cranor and Washington University. 5 * Copyright (c) 1991, 1993 The Regents of the University of California. 6 * Copyright (c) 1988 University of Utah. 7 * 8 * All rights reserved. 9 * 10 * This code is derived from software contributed to Berkeley by 11 * the Systems Programming Group of the University of Utah Computer 12 * Science Department. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. All advertising materials mentioning features or use of this software 23 * must display the following acknowledgement: 24 * This product includes software developed by Charles D. Cranor, 25 * Washington University, the University of California, Berkeley and 26 * its contributors. 27 * 4. Neither the name of the University nor the names of its contributors 28 * may be used to endorse or promote products derived from this software 29 * without specific prior written permission. 30 * 31 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 32 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 33 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 34 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 35 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 39 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 40 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 41 * SUCH DAMAGE. 42 * 43 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$ 44 * @(#)vm_unix.c 8.1 (Berkeley) 6/11/93 45 * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp 46 */ 47 48 /* 49 * uvm_unix.c: traditional sbrk/grow interface to vm. 50 */ 51 52 #include <sys/cdefs.h> 53 __KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.43 2009/12/15 06:15:11 matt Exp $"); 54 55 #include "opt_pax.h" 56 57 #include <sys/param.h> 58 #include <sys/systm.h> 59 #include <sys/proc.h> 60 #include <sys/resourcevar.h> 61 62 #include <sys/mount.h> 63 #include <sys/syscallargs.h> 64 65 #ifdef PAX_MPROTECT 66 #include <sys/pax.h> 67 #endif /* PAX_MPROTECT */ 68 69 #include <uvm/uvm.h> 70 71 /* 72 * sys_obreak: set break 73 */ 74 75 int 76 sys_obreak(struct lwp *l, const struct sys_obreak_args *uap, register_t *retval) 77 { 78 /* { 79 syscallarg(char *) nsize; 80 } */ 81 struct proc *p = l->l_proc; 82 struct vmspace *vm = p->p_vmspace; 83 vaddr_t new, old; 84 int error; 85 86 mutex_enter(&p->p_auxlock); 87 old = (vaddr_t)vm->vm_daddr; 88 new = round_page((vaddr_t)SCARG(uap, nsize)); 89 if (new == 0 || 90 ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old)) { 91 mutex_exit(&p->p_auxlock); 92 return (ENOMEM); 93 } 94 95 old = round_page(old + ptoa(vm->vm_dsize)); 96 97 if (new == old) { 98 mutex_exit(&p->p_auxlock); 99 return (0); 100 } 101 102 /* 103 * grow or shrink? 104 */ 105 106 if (new > old) { 107 vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE; 108 vm_prot_t maxprot = UVM_PROT_ALL; 109 110 #ifdef PAX_MPROTECT 111 pax_mprotect(l, &prot, &maxprot); 112 #endif /* PAX_MPROTECT */ 113 114 error = uvm_map(&vm->vm_map, &old, new - old, NULL, 115 UVM_UNKNOWN_OFFSET, 0, 116 UVM_MAPFLAG(prot, maxprot, 117 UVM_INH_COPY, 118 UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| 119 UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 120 if (error) { 121 #ifdef DEBUG 122 uprintf("sbrk: grow %#"PRIxVADDR" failed, error = %d\n", 123 new - old, error); 124 #endif 125 mutex_exit(&p->p_auxlock); 126 return (error); 127 } 128 vm->vm_dsize += atop(new - old); 129 } else { 130 uvm_deallocate(&vm->vm_map, new, old - new); 131 vm->vm_dsize -= atop(old - new); 132 } 133 mutex_exit(&p->p_auxlock); 134 135 return (0); 136 } 137 138 /* 139 * uvm_grow: enlarge the "stack segment" to include sp. 140 */ 141 142 int 143 uvm_grow(struct proc *p, vaddr_t sp) 144 { 145 struct vmspace *vm = p->p_vmspace; 146 vsize_t nss; 147 148 /* 149 * For user defined stacks (from sendsig). 150 */ 151 #ifdef __MACHINE_STACK_GROWS_UP 152 if (sp < (vaddr_t)vm->vm_minsaddr) 153 #else 154 if (sp < (vaddr_t)vm->vm_maxsaddr) 155 #endif 156 return (0); 157 158 /* 159 * For common case of already allocated (from trap). 160 */ 161 #ifdef __MACHINE_STACK_GROWS_UP 162 if (sp < USRSTACK + ctob(vm->vm_ssize)) 163 #else 164 if (sp >= USRSTACK - ctob(vm->vm_ssize)) 165 #endif 166 return (1); 167 168 /* 169 * Really need to check vs limit and increment stack size if ok. 170 */ 171 #ifdef __MACHINE_STACK_GROWS_UP 172 nss = btoc(sp - USRSTACK); 173 #else 174 nss = btoc(USRSTACK - sp); 175 #endif 176 if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 177 return (0); 178 vm->vm_ssize = nss; 179 return (1); 180 } 181 182 /* 183 * sys_oadvise: old advice system call 184 */ 185 186 /* ARGSUSED */ 187 int 188 sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval) 189 { 190 #if 0 191 /* { 192 syscallarg(int) anom; 193 } */ 194 #endif 195 196 return (EINVAL); 197 } 198