1 /* 2 * Copyright (c) 1982, 1986, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. 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 * @(#)kern_subr.c 8.3 (Berkeley) 1/21/94 39 * $FreeBSD: src/sys/kern/kern_subr.c,v 1.31.2.2 2002/04/21 08:09:37 bde Exp $ 40 * $DragonFly: src/sys/kern/kern_subr.c,v 1.10 2003/08/03 12:29:05 hmp Exp $ 41 */ 42 43 #include "opt_ddb.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/proc.h> 49 #include <sys/malloc.h> 50 #include <sys/lock.h> 51 #include <sys/resourcevar.h> 52 #include <sys/vnode.h> 53 54 #include <vm/vm.h> 55 #include <vm/vm_page.h> 56 #include <vm/vm_map.h> 57 58 int 59 uiomove(cp, n, uio) 60 caddr_t cp; 61 int n; 62 struct uio *uio; 63 { 64 struct iovec *iov; 65 u_int cnt; 66 int error = 0; 67 int save = 0; 68 int baseticks = ticks; 69 70 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE, 71 ("uiomove: mode")); 72 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 73 ("uiomove proc")); 74 75 if (curproc) { 76 save = curproc->p_flag & P_DEADLKTREAT; 77 curproc->p_flag |= P_DEADLKTREAT; 78 } 79 80 while (n > 0 && uio->uio_resid) { 81 iov = uio->uio_iov; 82 cnt = iov->iov_len; 83 if (cnt == 0) { 84 uio->uio_iov++; 85 uio->uio_iovcnt--; 86 continue; 87 } 88 if (cnt > n) 89 cnt = n; 90 91 switch (uio->uio_segflg) { 92 93 case UIO_USERSPACE: 94 case UIO_USERISPACE: 95 if (ticks - baseticks >= hogticks) { 96 uio_yield(); 97 baseticks = ticks; 98 } 99 if (uio->uio_rw == UIO_READ) 100 error = copyout(cp, iov->iov_base, cnt); 101 else 102 error = copyin(iov->iov_base, cp, cnt); 103 if (error) 104 break; 105 break; 106 107 case UIO_SYSSPACE: 108 if (uio->uio_rw == UIO_READ) 109 bcopy((caddr_t)cp, iov->iov_base, cnt); 110 else 111 bcopy(iov->iov_base, (caddr_t)cp, cnt); 112 break; 113 case UIO_NOCOPY: 114 break; 115 } 116 iov->iov_base += cnt; 117 iov->iov_len -= cnt; 118 uio->uio_resid -= cnt; 119 uio->uio_offset += cnt; 120 cp += cnt; 121 n -= cnt; 122 } 123 if (curproc) 124 curproc->p_flag = (curproc->p_flag & ~P_DEADLKTREAT) | save; 125 return (error); 126 } 127 128 int 129 uiomoveco(cp, n, uio, obj) 130 caddr_t cp; 131 int n; 132 struct uio *uio; 133 struct vm_object *obj; 134 { 135 struct iovec *iov; 136 u_int cnt; 137 int error; 138 int baseticks = ticks; 139 140 KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE, 141 ("uiomoveco: mode")); 142 KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, 143 ("uiomoveco proc")); 144 145 while (n > 0 && uio->uio_resid) { 146 iov = uio->uio_iov; 147 cnt = iov->iov_len; 148 if (cnt == 0) { 149 uio->uio_iov++; 150 uio->uio_iovcnt--; 151 continue; 152 } 153 if (cnt > n) 154 cnt = n; 155 156 switch (uio->uio_segflg) { 157 158 case UIO_USERSPACE: 159 case UIO_USERISPACE: 160 if (ticks - baseticks >= hogticks) { 161 uio_yield(); 162 baseticks = ticks; 163 } 164 if (uio->uio_rw == UIO_READ) { 165 #ifdef ENABLE_VFS_IOOPT 166 if (vfs_ioopt && ((cnt & PAGE_MASK) == 0) && 167 ((((intptr_t) iov->iov_base) & PAGE_MASK) == 0) && 168 ((uio->uio_offset & PAGE_MASK) == 0) && 169 ((((intptr_t) cp) & PAGE_MASK) == 0)) { 170 error = vm_uiomove(&curproc->p_vmspace->vm_map, obj, 171 uio->uio_offset, cnt, 172 (vm_offset_t) iov->iov_base, NULL); 173 } else 174 #endif 175 { 176 error = copyout(cp, iov->iov_base, cnt); 177 } 178 } else { 179 error = copyin(iov->iov_base, cp, cnt); 180 } 181 if (error) 182 return (error); 183 break; 184 185 case UIO_SYSSPACE: 186 if (uio->uio_rw == UIO_READ) 187 bcopy((caddr_t)cp, iov->iov_base, cnt); 188 else 189 bcopy(iov->iov_base, (caddr_t)cp, cnt); 190 break; 191 case UIO_NOCOPY: 192 break; 193 } 194 iov->iov_base += cnt; 195 iov->iov_len -= cnt; 196 uio->uio_resid -= cnt; 197 uio->uio_offset += cnt; 198 cp += cnt; 199 n -= cnt; 200 } 201 return (0); 202 } 203 204 #ifdef ENABLE_VFS_IOOPT 205 206 int 207 uioread(n, uio, obj, nread) 208 int n; 209 struct uio *uio; 210 struct vm_object *obj; 211 int *nread; 212 { 213 int npagesmoved; 214 struct iovec *iov; 215 u_int cnt, tcnt; 216 int error; 217 int baseticks = ticks; 218 219 *nread = 0; 220 if (vfs_ioopt < 2) 221 return 0; 222 223 error = 0; 224 225 while (n > 0 && uio->uio_resid) { 226 iov = uio->uio_iov; 227 cnt = iov->iov_len; 228 if (cnt == 0) { 229 uio->uio_iov++; 230 uio->uio_iovcnt--; 231 continue; 232 } 233 if (cnt > n) 234 cnt = n; 235 236 if ((uio->uio_segflg == UIO_USERSPACE) && 237 ((((intptr_t) iov->iov_base) & PAGE_MASK) == 0) && 238 ((uio->uio_offset & PAGE_MASK) == 0) ) { 239 240 if (cnt < PAGE_SIZE) 241 break; 242 243 cnt &= ~PAGE_MASK; 244 245 if (ticks - baseticks >= hogticks) { 246 uio_yield(); 247 baseticks = ticks; 248 } 249 error = vm_uiomove(&curproc->p_vmspace->vm_map, obj, 250 uio->uio_offset, cnt, 251 (vm_offset_t) iov->iov_base, &npagesmoved); 252 253 if (npagesmoved == 0) 254 break; 255 256 tcnt = npagesmoved * PAGE_SIZE; 257 cnt = tcnt; 258 259 if (error) 260 break; 261 262 iov->iov_base += cnt; 263 iov->iov_len -= cnt; 264 uio->uio_resid -= cnt; 265 uio->uio_offset += cnt; 266 *nread += cnt; 267 n -= cnt; 268 } else { 269 break; 270 } 271 } 272 return error; 273 } 274 275 #endif 276 277 /* 278 * Give next character to user as result of read. 279 */ 280 int 281 ureadc(c, uio) 282 int c; 283 struct uio *uio; 284 { 285 struct iovec *iov; 286 287 again: 288 if (uio->uio_iovcnt == 0 || uio->uio_resid == 0) 289 panic("ureadc"); 290 iov = uio->uio_iov; 291 if (iov->iov_len == 0) { 292 uio->uio_iovcnt--; 293 uio->uio_iov++; 294 goto again; 295 } 296 switch (uio->uio_segflg) { 297 298 case UIO_USERSPACE: 299 if (subyte(iov->iov_base, c) < 0) 300 return (EFAULT); 301 break; 302 303 case UIO_SYSSPACE: 304 *iov->iov_base = c; 305 break; 306 307 case UIO_USERISPACE: 308 if (suibyte(iov->iov_base, c) < 0) 309 return (EFAULT); 310 break; 311 case UIO_NOCOPY: 312 break; 313 } 314 iov->iov_base++; 315 iov->iov_len--; 316 uio->uio_resid--; 317 uio->uio_offset++; 318 return (0); 319 } 320 321 #ifdef vax /* unused except by ct.c, other oddities XXX */ 322 /* 323 * Get next character written in by user from uio. 324 */ 325 int 326 uwritec(uio) 327 struct uio *uio; 328 { 329 struct iovec *iov; 330 int c; 331 332 if (uio->uio_resid <= 0) 333 return (-1); 334 again: 335 if (uio->uio_iovcnt <= 0) 336 panic("uwritec"); 337 iov = uio->uio_iov; 338 if (iov->iov_len == 0) { 339 uio->uio_iov++; 340 if (--uio->uio_iovcnt == 0) 341 return (-1); 342 goto again; 343 } 344 switch (uio->uio_segflg) { 345 346 case UIO_USERSPACE: 347 c = fubyte(iov->iov_base); 348 break; 349 350 case UIO_SYSSPACE: 351 c = *(u_char *) iov->iov_base; 352 break; 353 354 case UIO_USERISPACE: 355 c = fuibyte(iov->iov_base); 356 break; 357 } 358 if (c < 0) 359 return (-1); 360 iov->iov_base++; 361 iov->iov_len--; 362 uio->uio_resid--; 363 uio->uio_offset++; 364 return (c); 365 } 366 #endif /* vax */ 367 368 /* 369 * General routine to allocate a hash table. 370 */ 371 void * 372 hashinit(elements, type, hashmask) 373 int elements; 374 struct malloc_type *type; 375 u_long *hashmask; 376 { 377 long hashsize; 378 LIST_HEAD(generic, generic) *hashtbl; 379 int i; 380 381 if (elements <= 0) 382 panic("hashinit: bad elements"); 383 for (hashsize = 1; hashsize <= elements; hashsize <<= 1) 384 continue; 385 hashsize >>= 1; 386 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK); 387 for (i = 0; i < hashsize; i++) 388 LIST_INIT(&hashtbl[i]); 389 *hashmask = hashsize - 1; 390 return (hashtbl); 391 } 392 393 static int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531, 2039, 394 2557, 3067, 3583, 4093, 4603, 5119, 5623, 6143, 6653, 395 7159, 7673, 8191, 12281, 16381, 24571, 32749 }; 396 #define NPRIMES (sizeof(primes) / sizeof(primes[0])) 397 398 /* 399 * General routine to allocate a prime number sized hash table. 400 */ 401 void * 402 phashinit(elements, type, nentries) 403 int elements; 404 struct malloc_type *type; 405 u_long *nentries; 406 { 407 long hashsize; 408 LIST_HEAD(generic, generic) *hashtbl; 409 int i; 410 411 if (elements <= 0) 412 panic("phashinit: bad elements"); 413 for (i = 1, hashsize = primes[1]; hashsize <= elements;) { 414 i++; 415 if (i == NPRIMES) 416 break; 417 hashsize = primes[i]; 418 } 419 hashsize = primes[i - 1]; 420 hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK); 421 for (i = 0; i < hashsize; i++) 422 LIST_INIT(&hashtbl[i]); 423 *nentries = hashsize; 424 return (hashtbl); 425 } 426