1 /* $NetBSD: uvm_unix.c,v 1.38 2007/02/09 21:55:43 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 1.38 2007/02/09 21:55:43 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, void *v, register_t *retval) 77 { 78 struct sys_obreak_args /* { 79 syscallarg(char *) nsize; 80 } */ *uap = v; 81 struct proc *p = l->l_proc; 82 struct vmspace *vm = p->p_vmspace; 83 vaddr_t new, old; 84 int error; 85 86 old = (vaddr_t)vm->vm_daddr; 87 new = round_page((vaddr_t)SCARG(uap, nsize)); 88 if ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old) 89 return (ENOMEM); 90 91 old = round_page(old + ptoa(vm->vm_dsize)); 92 93 if (new == old) 94 return (0); 95 96 /* 97 * grow or shrink? 98 */ 99 100 if (new > old) { 101 vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE; 102 vm_prot_t maxprot = UVM_PROT_ALL; 103 104 #ifdef PAX_MPROTECT 105 pax_mprotect(l, &prot, &maxprot); 106 #endif /* PAX_MPROTECT */ 107 108 error = uvm_map(&vm->vm_map, &old, new - old, NULL, 109 UVM_UNKNOWN_OFFSET, 0, 110 UVM_MAPFLAG(prot, maxprot, 111 UVM_INH_COPY, 112 UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| 113 UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 114 if (error) { 115 uprintf("sbrk: grow %ld failed, error = %d\n", 116 new - old, error); 117 return (error); 118 } 119 vm->vm_dsize += atop(new - old); 120 } else { 121 uvm_deallocate(&vm->vm_map, new, old - new); 122 vm->vm_dsize -= atop(old - new); 123 } 124 return (0); 125 } 126 127 /* 128 * uvm_grow: enlarge the "stack segment" to include sp. 129 */ 130 131 int 132 uvm_grow(struct proc *p, vaddr_t sp) 133 { 134 struct vmspace *vm = p->p_vmspace; 135 vsize_t nss; 136 137 /* 138 * For user defined stacks (from sendsig). 139 */ 140 #ifdef __MACHINE_STACK_GROWS_UP 141 if (sp < (vaddr_t)vm->vm_minsaddr) 142 #else 143 if (sp < (vaddr_t)vm->vm_maxsaddr) 144 #endif 145 return (0); 146 147 /* 148 * For common case of already allocated (from trap). 149 */ 150 #ifdef __MACHINE_STACK_GROWS_UP 151 if (sp < USRSTACK + ctob(vm->vm_ssize)) 152 #else 153 if (sp >= USRSTACK - ctob(vm->vm_ssize)) 154 #endif 155 return (1); 156 157 /* 158 * Really need to check vs limit and increment stack size if ok. 159 */ 160 #ifdef __MACHINE_STACK_GROWS_UP 161 nss = btoc(sp - USRSTACK); 162 #else 163 nss = btoc(USRSTACK - sp); 164 #endif 165 if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 166 return (0); 167 vm->vm_ssize = nss; 168 return (1); 169 } 170 171 /* 172 * sys_oadvise: old advice system call 173 */ 174 175 /* ARGSUSED */ 176 int 177 sys_ovadvise(struct lwp *l, void *v, register_t *retval) 178 { 179 #if 0 180 struct sys_ovadvise_args /* { 181 syscallarg(int) anom; 182 } */ *uap = v; 183 #endif 184 185 return (EINVAL); 186 } 187