uvm_unix.c revision 1.43.4.1
1 /* $NetBSD: uvm_unix.c,v 1.43.4.1 2011/03/05 20:56:38 rmind 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. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$ 39 * @(#)vm_unix.c 8.1 (Berkeley) 6/11/93 40 * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp 41 */ 42 43 /* 44 * uvm_unix.c: traditional sbrk/grow interface to vm. 45 */ 46 47 #include <sys/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.43.4.1 2011/03/05 20:56:38 rmind Exp $"); 49 50 #include "opt_pax.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/proc.h> 55 #include <sys/resourcevar.h> 56 57 #include <sys/mount.h> 58 #include <sys/syscallargs.h> 59 60 #ifdef PAX_MPROTECT 61 #include <sys/pax.h> 62 #endif /* PAX_MPROTECT */ 63 64 #include <uvm/uvm.h> 65 66 /* 67 * sys_obreak: set break 68 */ 69 70 int 71 sys_obreak(struct lwp *l, const struct sys_obreak_args *uap, register_t *retval) 72 { 73 /* { 74 syscallarg(char *) nsize; 75 } */ 76 struct proc *p = l->l_proc; 77 struct vmspace *vm = p->p_vmspace; 78 vaddr_t new, old; 79 int error; 80 81 mutex_enter(&p->p_auxlock); 82 old = (vaddr_t)vm->vm_daddr; 83 new = round_page((vaddr_t)SCARG(uap, nsize)); 84 if (new == 0 || 85 ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old)) { 86 mutex_exit(&p->p_auxlock); 87 return (ENOMEM); 88 } 89 90 old = round_page(old + ptoa(vm->vm_dsize)); 91 92 if (new == old) { 93 mutex_exit(&p->p_auxlock); 94 return (0); 95 } 96 97 /* 98 * grow or shrink? 99 */ 100 101 if (new > old) { 102 vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE; 103 vm_prot_t maxprot = UVM_PROT_ALL; 104 105 #ifdef PAX_MPROTECT 106 pax_mprotect(l, &prot, &maxprot); 107 #endif /* PAX_MPROTECT */ 108 109 error = uvm_map(&vm->vm_map, &old, new - old, NULL, 110 UVM_UNKNOWN_OFFSET, 0, 111 UVM_MAPFLAG(prot, maxprot, 112 UVM_INH_COPY, 113 UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| 114 UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 115 if (error) { 116 #ifdef DEBUG 117 uprintf("sbrk: grow %#"PRIxVADDR" failed, error = %d\n", 118 new - old, error); 119 #endif 120 mutex_exit(&p->p_auxlock); 121 return (error); 122 } 123 vm->vm_dsize += atop(new - old); 124 } else { 125 uvm_deallocate(&vm->vm_map, new, old - new); 126 vm->vm_dsize -= atop(old - new); 127 } 128 mutex_exit(&p->p_auxlock); 129 130 return (0); 131 } 132 133 /* 134 * uvm_grow: enlarge the "stack segment" to include sp. 135 */ 136 137 int 138 uvm_grow(struct proc *p, vaddr_t sp) 139 { 140 struct vmspace *vm = p->p_vmspace; 141 vsize_t nss; 142 143 /* 144 * For user defined stacks (from sendsig). 145 */ 146 #ifdef __MACHINE_STACK_GROWS_UP 147 if (sp < (vaddr_t)vm->vm_minsaddr) 148 #else 149 if (sp < (vaddr_t)vm->vm_maxsaddr) 150 #endif 151 return (0); 152 153 /* 154 * For common case of already allocated (from trap). 155 */ 156 #ifdef __MACHINE_STACK_GROWS_UP 157 if (sp < USRSTACK + ctob(vm->vm_ssize)) 158 #else 159 if (sp >= USRSTACK - ctob(vm->vm_ssize)) 160 #endif 161 return (1); 162 163 /* 164 * Really need to check vs limit and increment stack size if ok. 165 */ 166 #ifdef __MACHINE_STACK_GROWS_UP 167 nss = btoc(sp - USRSTACK); 168 #else 169 nss = btoc(USRSTACK - sp); 170 #endif 171 if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 172 return (0); 173 vm->vm_ssize = nss; 174 return (1); 175 } 176 177 /* 178 * sys_oadvise: old advice system call 179 */ 180 181 /* ARGSUSED */ 182 int 183 sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval) 184 { 185 #if 0 186 /* { 187 syscallarg(int) anom; 188 } */ 189 #endif 190 191 return (EINVAL); 192 } 193
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