1 /* 2 * Copyright (c) 2000, 2001 Boris Popov 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Boris Popov. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD: src/sys/kern/subr_mchain.c,v 1.2.2.2 2002/04/13 12:46:40 bp Exp $ 33 */ 34 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/errno.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/module.h> 43 #include <sys/uio.h> 44 45 #include <sys/mchain.h> 46 47 MODULE_VERSION(libmchain, 1); 48 49 #define MBERROR(format, args...) printf("%s(%d): "format, __FUNCTION__ , \ 50 __LINE__ ,## args) 51 52 #define MBPANIC(format, args...) printf("%s(%d): "format, __FUNCTION__ , \ 53 __LINE__ ,## args) 54 55 /* 56 * Various helper functions 57 */ 58 int 59 m_fixhdr(struct mbuf *m0) 60 { 61 struct mbuf *m = m0; 62 int len = 0; 63 64 while (m) { 65 len += m->m_len; 66 m = m->m_next; 67 } 68 m0->m_pkthdr.len = len; 69 return len; 70 } 71 72 int 73 mb_init(struct mbchain *mbp) 74 { 75 struct mbuf *m; 76 77 m = m_gethdr(M_WAITOK, MT_DATA); 78 if (m == NULL) 79 return ENOBUFS; 80 m->m_pkthdr.rcvif = NULL; 81 m->m_len = 0; 82 mb_initm(mbp, m); 83 return 0; 84 } 85 86 void 87 mb_initm(struct mbchain *mbp, struct mbuf *m) 88 { 89 bzero(mbp, sizeof(*mbp)); 90 mbp->mb_top = mbp->mb_cur = m; 91 mbp->mb_mleft = M_TRAILINGSPACE(m); 92 } 93 94 void 95 mb_done(struct mbchain *mbp) 96 { 97 if (mbp->mb_top) { 98 m_freem(mbp->mb_top); 99 mbp->mb_top = NULL; 100 } 101 } 102 103 struct mbuf * 104 mb_detach(struct mbchain *mbp) 105 { 106 struct mbuf *m; 107 108 m = mbp->mb_top; 109 mbp->mb_top = NULL; 110 return m; 111 } 112 113 int 114 mb_fixhdr(struct mbchain *mbp) 115 { 116 return mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top); 117 } 118 119 /* 120 * Check if object of size 'size' fit to the current position and 121 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s). 122 * Return pointer to the object placeholder or NULL if any error occured. 123 * Note: size should be <= MLEN 124 */ 125 caddr_t 126 mb_reserve(struct mbchain *mbp, int size) 127 { 128 struct mbuf *m, *mn; 129 caddr_t bpos; 130 131 if (size > MLEN) 132 panic("mb_reserve: size = %d\n", size); 133 m = mbp->mb_cur; 134 if (mbp->mb_mleft < size) { 135 mn = m_get(M_WAITOK, MT_DATA); 136 if (mn == NULL) 137 return NULL; 138 mbp->mb_cur = m->m_next = mn; 139 m = mn; 140 m->m_len = 0; 141 mbp->mb_mleft = M_TRAILINGSPACE(m); 142 } 143 mbp->mb_mleft -= size; 144 mbp->mb_count += size; 145 bpos = mtod(m, caddr_t) + m->m_len; 146 m->m_len += size; 147 return bpos; 148 } 149 150 int 151 mb_put_uint8(struct mbchain *mbp, u_int8_t x) 152 { 153 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 154 } 155 156 int 157 mb_put_uint16be(struct mbchain *mbp, u_int16_t x) 158 { 159 x = htobes(x); 160 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 161 } 162 163 int 164 mb_put_uint16le(struct mbchain *mbp, u_int16_t x) 165 { 166 x = htoles(x); 167 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 168 } 169 170 int 171 mb_put_uint32be(struct mbchain *mbp, u_int32_t x) 172 { 173 x = htobel(x); 174 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 175 } 176 177 int 178 mb_put_uint32le(struct mbchain *mbp, u_int32_t x) 179 { 180 x = htolel(x); 181 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 182 } 183 184 int 185 mb_put_int64be(struct mbchain *mbp, int64_t x) 186 { 187 x = htobeq(x); 188 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 189 } 190 191 int 192 mb_put_int64le(struct mbchain *mbp, int64_t x) 193 { 194 x = htoleq(x); 195 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 196 } 197 198 int 199 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type) 200 { 201 struct mbuf *m; 202 caddr_t dst; 203 c_caddr_t src; 204 int cplen, error, mleft, count; 205 206 m = mbp->mb_cur; 207 mleft = mbp->mb_mleft; 208 209 while (size > 0) { 210 if (mleft == 0) { 211 if (m->m_next == NULL) { 212 m = m_getm(m, size, M_WAITOK, MT_DATA); 213 if (m == NULL) 214 return ENOBUFS; 215 } 216 m = m->m_next; 217 mleft = M_TRAILINGSPACE(m); 218 continue; 219 } 220 cplen = mleft > size ? size : mleft; 221 dst = mtod(m, caddr_t) + m->m_len; 222 switch (type) { 223 case MB_MCUSTOM: 224 error = mbp->mb_copy(mbp, source, dst, cplen); 225 if (error) 226 return error; 227 break; 228 case MB_MINLINE: 229 for (src = source, count = cplen; count; count--) 230 *dst++ = *src++; 231 break; 232 case MB_MSYSTEM: 233 bcopy(source, dst, cplen); 234 break; 235 case MB_MUSER: 236 error = copyin(source, dst, cplen); 237 if (error) 238 return error; 239 break; 240 case MB_MZERO: 241 bzero(dst, cplen); 242 break; 243 } 244 size -= cplen; 245 source += cplen; 246 m->m_len += cplen; 247 mleft -= cplen; 248 mbp->mb_count += cplen; 249 } 250 mbp->mb_cur = m; 251 mbp->mb_mleft = mleft; 252 return 0; 253 } 254 255 int 256 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m) 257 { 258 mbp->mb_cur->m_next = m; 259 while (m) { 260 mbp->mb_count += m->m_len; 261 if (m->m_next == NULL) 262 break; 263 m = m->m_next; 264 } 265 mbp->mb_mleft = M_TRAILINGSPACE(m); 266 mbp->mb_cur = m; 267 return 0; 268 } 269 270 /* 271 * copies a uio scatter/gather list to an mbuf chain. 272 */ 273 int 274 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size) 275 { 276 long left; 277 int mtype, error; 278 279 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 280 281 while (size > 0 && uiop->uio_resid) { 282 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 283 return EFBIG; 284 left = uiop->uio_iov->iov_len; 285 if (left == 0) { 286 uiop->uio_iov++; 287 uiop->uio_iovcnt--; 288 continue; 289 } 290 if (left > size) 291 left = size; 292 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype); 293 if (error) 294 return error; 295 uiop->uio_offset += left; 296 uiop->uio_resid -= left; 297 uiop->uio_iov->iov_base += left; 298 uiop->uio_iov->iov_len -= left; 299 size -= left; 300 } 301 return 0; 302 } 303 304 /* 305 * Routines for fetching data from an mbuf chain 306 */ 307 int 308 md_init(struct mdchain *mdp) 309 { 310 struct mbuf *m; 311 312 m = m_gethdr(M_WAITOK, MT_DATA); 313 if (m == NULL) 314 return ENOBUFS; 315 m->m_pkthdr.rcvif = NULL; 316 m->m_len = 0; 317 md_initm(mdp, m); 318 return 0; 319 } 320 321 void 322 md_initm(struct mdchain *mdp, struct mbuf *m) 323 { 324 bzero(mdp, sizeof(*mdp)); 325 mdp->md_top = mdp->md_cur = m; 326 mdp->md_pos = mtod(m, u_char*); 327 } 328 329 void 330 md_done(struct mdchain *mdp) 331 { 332 if (mdp->md_top) { 333 m_freem(mdp->md_top); 334 mdp->md_top = NULL; 335 } 336 } 337 338 /* 339 * Append a separate mbuf chain. It is caller responsibility to prevent 340 * multiple calls to fetch/record routines. 341 */ 342 void 343 md_append_record(struct mdchain *mdp, struct mbuf *top) 344 { 345 struct mbuf *m; 346 347 if (mdp->md_top == NULL) { 348 md_initm(mdp, top); 349 return; 350 } 351 m = mdp->md_top; 352 while (m->m_nextpkt) 353 m = m->m_nextpkt; 354 m->m_nextpkt = top; 355 top->m_nextpkt = NULL; 356 return; 357 } 358 359 /* 360 * Put next record in place of existing 361 */ 362 int 363 md_next_record(struct mdchain *mdp) 364 { 365 struct mbuf *m; 366 367 if (mdp->md_top == NULL) 368 return ENOENT; 369 m = mdp->md_top->m_nextpkt; 370 md_done(mdp); 371 if (m == NULL) 372 return ENOENT; 373 md_initm(mdp, m); 374 return 0; 375 } 376 377 int 378 md_get_uint8(struct mdchain *mdp, u_int8_t *x) 379 { 380 return md_get_mem(mdp, x, 1, MB_MINLINE); 381 } 382 383 int 384 md_get_uint16(struct mdchain *mdp, u_int16_t *x) 385 { 386 return md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE); 387 } 388 389 int 390 md_get_uint16le(struct mdchain *mdp, u_int16_t *x) 391 { 392 u_int16_t v; 393 int error = md_get_uint16(mdp, &v); 394 395 *x = letohs(v); 396 return error; 397 } 398 399 int 400 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) { 401 u_int16_t v; 402 int error = md_get_uint16(mdp, &v); 403 404 *x = betohs(v); 405 return error; 406 } 407 408 int 409 md_get_uint32(struct mdchain *mdp, u_int32_t *x) 410 { 411 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE); 412 } 413 414 int 415 md_get_uint32be(struct mdchain *mdp, u_int32_t *x) 416 { 417 u_int32_t v; 418 int error; 419 420 error = md_get_uint32(mdp, &v); 421 *x = betohl(v); 422 return error; 423 } 424 425 int 426 md_get_uint32le(struct mdchain *mdp, u_int32_t *x) 427 { 428 u_int32_t v; 429 int error; 430 431 error = md_get_uint32(mdp, &v); 432 *x = letohl(v); 433 return error; 434 } 435 436 int 437 md_get_int64(struct mdchain *mdp, int64_t *x) 438 { 439 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE); 440 } 441 442 int 443 md_get_int64be(struct mdchain *mdp, int64_t *x) 444 { 445 int64_t v; 446 int error; 447 448 error = md_get_int64(mdp, &v); 449 *x = betohq(v); 450 return error; 451 } 452 453 int 454 md_get_int64le(struct mdchain *mdp, int64_t *x) 455 { 456 int64_t v; 457 int error; 458 459 error = md_get_int64(mdp, &v); 460 *x = letohq(v); 461 return error; 462 } 463 464 int 465 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type) 466 { 467 struct mbuf *m = mdp->md_cur; 468 int error; 469 u_int count; 470 u_char *s; 471 472 while (size > 0) { 473 if (m == NULL) { 474 MBERROR("incomplete copy\n"); 475 return EBADRPC; 476 } 477 s = mdp->md_pos; 478 count = mtod(m, u_char*) + m->m_len - s; 479 if (count == 0) { 480 mdp->md_cur = m = m->m_next; 481 if (m) 482 s = mdp->md_pos = mtod(m, caddr_t); 483 continue; 484 } 485 if (count > size) 486 count = size; 487 size -= count; 488 mdp->md_pos += count; 489 if (target == NULL) 490 continue; 491 switch (type) { 492 case MB_MUSER: 493 error = copyout(s, target, count); 494 if (error) 495 return error; 496 break; 497 case MB_MSYSTEM: 498 bcopy(s, target, count); 499 break; 500 case MB_MINLINE: 501 while (count--) 502 *target++ = *s++; 503 continue; 504 } 505 target += count; 506 } 507 return 0; 508 } 509 510 int 511 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret) 512 { 513 struct mbuf *m = mdp->md_cur, *rm; 514 515 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, M_WAITOK); 516 if (rm == NULL) 517 return EBADRPC; 518 md_get_mem(mdp, NULL, size, MB_MZERO); 519 *ret = rm; 520 return 0; 521 } 522 523 int 524 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size) 525 { 526 char *uiocp; 527 long left; 528 int mtype, error; 529 530 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 531 while (size > 0 && uiop->uio_resid) { 532 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 533 return EFBIG; 534 left = uiop->uio_iov->iov_len; 535 if (left == 0) { 536 uiop->uio_iov++; 537 uiop->uio_iovcnt--; 538 continue; 539 } 540 uiocp = uiop->uio_iov->iov_base; 541 if (left > size) 542 left = size; 543 error = md_get_mem(mdp, uiocp, left, mtype); 544 if (error) 545 return error; 546 uiop->uio_offset += left; 547 uiop->uio_resid -= left; 548 uiop->uio_iov->iov_base += left; 549 uiop->uio_iov->iov_len -= left; 550 size -= left; 551 } 552 return 0; 553 } 554