1 /* $OpenBSD: uvm_unix.c,v 1.51 2014/11/16 12:31:01 deraadt Exp $ */ 2 /* $NetBSD: uvm_unix.c,v 1.18 2000/09/13 15:00:25 thorpej Exp $ */ 3 4 /* 5 * Copyright (c) 1997 Charles D. Cranor and Washington University. 6 * Copyright (c) 1991, 1993 The Regents of the University of California. 7 * Copyright (c) 1988 University of Utah. 8 * 9 * All rights reserved. 10 * 11 * This code is derived from software contributed to Berkeley by 12 * the Systems Programming Group of the University of Utah Computer 13 * Science Department. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$ 40 * @(#)vm_unix.c 8.1 (Berkeley) 6/11/93 41 * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp 42 */ 43 44 /* 45 * uvm_unix.c: traditional sbrk/grow interface to vm. 46 */ 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/proc.h> 51 #include <sys/resourcevar.h> 52 #include <sys/vnode.h> 53 #include <sys/core.h> 54 55 #include <sys/mount.h> 56 #include <sys/syscallargs.h> 57 58 #include <uvm/uvm.h> 59 60 /* 61 * sys_obreak: set break 62 */ 63 64 int 65 sys_obreak(struct proc *p, void *v, register_t *retval) 66 { 67 struct sys_obreak_args /* { 68 syscallarg(char *) nsize; 69 } */ *uap = v; 70 struct vmspace *vm = p->p_vmspace; 71 vaddr_t new, old, base; 72 int error; 73 74 base = (vaddr_t)vm->vm_daddr; 75 new = round_page((vaddr_t)SCARG(uap, nsize)); 76 if (new < base || (new - base) > p->p_rlimit[RLIMIT_DATA].rlim_cur) 77 return (ENOMEM); 78 79 old = round_page(base + ptoa(vm->vm_dsize)); 80 81 if (new == old) 82 return (0); 83 84 /* grow or shrink? */ 85 if (new > old) { 86 error = uvm_map(&vm->vm_map, &old, new - old, NULL, 87 UVM_UNKNOWN_OFFSET, 0, 88 UVM_MAPFLAG(PROT_READ | PROT_WRITE, PROT_MASK, UVM_INH_COPY, 89 POSIX_MADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| 90 UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); 91 if (error) { 92 uprintf("sbrk: grow %ld failed, error = %d\n", 93 new - old, error); 94 return (ENOMEM); 95 } 96 vm->vm_dsize += atop(new - old); 97 } else { 98 uvm_deallocate(&vm->vm_map, new, old - new); 99 vm->vm_dsize -= atop(old - new); 100 } 101 102 return (0); 103 } 104 105 /* 106 * uvm_grow: enlarge the "stack segment" to include sp. 107 */ 108 void 109 uvm_grow(struct proc *p, vaddr_t sp) 110 { 111 struct vmspace *vm = p->p_vmspace; 112 int si; 113 114 /* For user defined stacks (from sendsig). */ 115 if (sp < (vaddr_t)vm->vm_maxsaddr) 116 return; 117 118 /* For common case of already allocated (from trap). */ 119 #ifdef MACHINE_STACK_GROWS_UP 120 if (sp < USRSTACK + ptoa(vm->vm_ssize)) 121 #else 122 if (sp >= USRSTACK - ptoa(vm->vm_ssize)) 123 #endif 124 return; 125 126 /* Really need to check vs limit and increment stack size if ok. */ 127 #ifdef MACHINE_STACK_GROWS_UP 128 si = atop(sp - USRSTACK) - vm->vm_ssize + 1; 129 #else 130 si = atop(USRSTACK - sp) - vm->vm_ssize; 131 #endif 132 if (vm->vm_ssize + si <= atop(p->p_rlimit[RLIMIT_STACK].rlim_cur)) 133 vm->vm_ssize += si; 134 } 135 136 #ifndef SMALL_KERNEL 137 138 /* 139 * uvm_coredump: dump core! 140 */ 141 142 int 143 uvm_coredump(struct proc *p, struct vnode *vp, struct ucred *cred, 144 struct core *chdr) 145 { 146 struct vmspace *vm = p->p_vmspace; 147 vm_map_t map = &vm->vm_map; 148 vm_map_entry_t entry, safe; 149 vaddr_t start, end, top; 150 struct coreseg cseg; 151 off_t offset, coffset; 152 int csize, chunk, flag, error = 0; 153 154 offset = chdr->c_hdrsize + chdr->c_seghdrsize + chdr->c_cpusize; 155 156 RB_FOREACH_SAFE(entry, uvm_map_addr, &map->addr, safe) { 157 /* should never happen for a user process */ 158 if (UVM_ET_ISSUBMAP(entry)) { 159 panic("uvm_coredump: user process with submap?"); 160 } 161 162 if (!(entry->protection & PROT_WRITE) && 163 entry->start != p->p_p->ps_sigcode) 164 continue; 165 166 /* Don't dump mmaped devices. */ 167 if (entry->object.uvm_obj != NULL && 168 UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) 169 continue; 170 171 start = entry->start; 172 end = entry->end; 173 174 if (start >= VM_MAXUSER_ADDRESS) 175 continue; 176 177 if (end > VM_MAXUSER_ADDRESS) 178 end = VM_MAXUSER_ADDRESS; 179 180 #ifdef MACHINE_STACK_GROWS_UP 181 if (USRSTACK <= start && start < (USRSTACK + MAXSSIZ)) { 182 top = round_page(USRSTACK + ptoa(vm->vm_ssize)); 183 if (end > top) 184 end = top; 185 186 if (start >= end) 187 continue; 188 #else 189 if (start >= (vaddr_t)vm->vm_maxsaddr) { 190 top = trunc_page(USRSTACK - ptoa(vm->vm_ssize)); 191 if (start < top) 192 start = top; 193 194 if (start >= end) 195 continue; 196 #endif 197 flag = CORE_STACK; 198 } else 199 flag = CORE_DATA; 200 201 /* Set up a new core file segment. */ 202 CORE_SETMAGIC(cseg, CORESEGMAGIC, CORE_GETMID(*chdr), flag); 203 cseg.c_addr = start; 204 cseg.c_size = end - start; 205 206 error = vn_rdwr(UIO_WRITE, vp, 207 (caddr_t)&cseg, chdr->c_seghdrsize, 208 offset, UIO_SYSSPACE, IO_UNIT, cred, NULL, p); 209 /* 210 * We might get an EFAULT on objects mapped beyond 211 * EOF. Ignore the error. 212 */ 213 if (error && error != EFAULT) 214 break; 215 216 offset += chdr->c_seghdrsize; 217 218 coffset = 0; 219 csize = (int)cseg.c_size; 220 do { 221 if (p->p_siglist & sigmask(SIGKILL)) 222 return (EINTR); 223 224 /* Rest of the loop sleeps with lock held, so... */ 225 yield(); 226 227 chunk = MIN(csize, MAXPHYS); 228 error = vn_rdwr(UIO_WRITE, vp, 229 (caddr_t)(u_long)cseg.c_addr + coffset, 230 chunk, offset + coffset, UIO_USERSPACE, 231 IO_UNIT, cred, NULL, p); 232 if (error) 233 return (error); 234 235 coffset += chunk; 236 csize -= chunk; 237 } while (csize > 0); 238 offset += cseg.c_size; 239 240 /* Discard the memory */ 241 uvm_unmap(map, cseg.c_addr, cseg.c_addr + cseg.c_size); 242 243 chdr->c_nseg++; 244 } 245 246 return (error); 247 } 248 249 int 250 uvm_coredump_walkmap(struct proc *p, void *iocookie, 251 int (*func)(struct proc *, void *, struct uvm_coredump_state *), 252 void *cookie) 253 { 254 struct uvm_coredump_state state; 255 struct vmspace *vm = p->p_vmspace; 256 struct vm_map *map = &vm->vm_map; 257 struct vm_map_entry *entry; 258 vaddr_t top; 259 int error; 260 261 RB_FOREACH(entry, uvm_map_addr, &map->addr) { 262 state.cookie = cookie; 263 state.prot = entry->protection; 264 state.flags = 0; 265 266 /* should never happen for a user process */ 267 if (UVM_ET_ISSUBMAP(entry)) { 268 panic("uvm_coredump: user process with submap?"); 269 } 270 271 if (!(entry->protection & PROT_WRITE) && 272 entry->start != p->p_p->ps_sigcode) 273 continue; 274 275 /* Don't dump mmaped devices. */ 276 if (entry->object.uvm_obj != NULL && 277 UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) 278 continue; 279 280 state.start = entry->start; 281 state.realend = entry->end; 282 state.end = entry->end; 283 284 if (state.start >= VM_MAXUSER_ADDRESS) 285 continue; 286 287 if (state.end > VM_MAXUSER_ADDRESS) 288 state.end = VM_MAXUSER_ADDRESS; 289 290 #ifdef MACHINE_STACK_GROWS_UP 291 if (USRSTACK <= state.start && 292 state.start < (USRSTACK + MAXSSIZ)) { 293 top = round_page(USRSTACK + ptoa(vm->vm_ssize)); 294 if (state.end > top) 295 state.end = top; 296 297 if (state.start >= state.end) 298 continue; 299 #else 300 if (state.start >= (vaddr_t)vm->vm_maxsaddr) { 301 top = trunc_page(USRSTACK - ptoa(vm->vm_ssize)); 302 if (state.start < top) 303 state.start = top; 304 305 if (state.start >= state.end) 306 continue; 307 #endif 308 state.flags |= UVM_COREDUMP_STACK; 309 } 310 311 error = (*func)(p, iocookie, &state); 312 if (error) 313 return (error); 314 } 315 316 return (0); 317 } 318 319 #endif /* !SMALL_KERNEL */ 320