1 /* $NetBSD: uvm_unix.c,v 1.40 2008/01/02 11:49:21 ad 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 1.40 2008/01/02 11:49:21 ad 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 - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old) { 90 mutex_exit(&p->p_auxlock); 91 return (ENOMEM); 92 } 93 94 old = round_page(old + ptoa(vm->vm_dsize)); 95 96 if (new == old) { 97 mutex_exit(&p->p_auxlock); 98 return (0); 99 } 100 101 /* 102 * grow or shrink? 103 */ 104 105 if (new > old) { 106 vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE; 107 vm_prot_t maxprot = UVM_PROT_ALL; 108 109 #ifdef PAX_MPROTECT 110 pax_mprotect(l, &prot, &maxprot); 111 #endif /* PAX_MPROTECT */ 112 113 error = uvm_map(&vm->vm_map, &old, new - old, NULL, 114 UVM_UNKNOWN_OFFSET, 0, 115 UVM_MAPFLAG(prot, maxprot, 116 UVM_INH_COPY, 117 UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| 118 UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 119 if (error) { 120 uprintf("sbrk: grow %ld failed, error = %d\n", 121 new - old, error); 122 mutex_exit(&p->p_auxlock); 123 return (error); 124 } 125 vm->vm_dsize += atop(new - old); 126 } else { 127 uvm_deallocate(&vm->vm_map, new, old - new); 128 vm->vm_dsize -= atop(old - new); 129 } 130 mutex_exit(&p->p_auxlock); 131 132 return (0); 133 } 134 135 /* 136 * uvm_grow: enlarge the "stack segment" to include sp. 137 */ 138 139 int 140 uvm_grow(struct proc *p, vaddr_t sp) 141 { 142 struct vmspace *vm = p->p_vmspace; 143 vsize_t nss; 144 145 /* 146 * For user defined stacks (from sendsig). 147 */ 148 #ifdef __MACHINE_STACK_GROWS_UP 149 if (sp < (vaddr_t)vm->vm_minsaddr) 150 #else 151 if (sp < (vaddr_t)vm->vm_maxsaddr) 152 #endif 153 return (0); 154 155 /* 156 * For common case of already allocated (from trap). 157 */ 158 #ifdef __MACHINE_STACK_GROWS_UP 159 if (sp < USRSTACK + ctob(vm->vm_ssize)) 160 #else 161 if (sp >= USRSTACK - ctob(vm->vm_ssize)) 162 #endif 163 return (1); 164 165 /* 166 * Really need to check vs limit and increment stack size if ok. 167 */ 168 #ifdef __MACHINE_STACK_GROWS_UP 169 nss = btoc(sp - USRSTACK); 170 #else 171 nss = btoc(USRSTACK - sp); 172 #endif 173 if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 174 return (0); 175 vm->vm_ssize = nss; 176 return (1); 177 } 178 179 /* 180 * sys_oadvise: old advice system call 181 */ 182 183 /* ARGSUSED */ 184 int 185 sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval) 186 { 187 #if 0 188 /* { 189 syscallarg(int) anom; 190 } */ 191 #endif 192 193 return (EINVAL); 194 } 195