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 * 4. Neither the name of the author nor the names of any co-contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: src/sys/kern/subr_mchain.c,v 1.2.2.2 2002/04/13 12:46:40 bp Exp $ 30 */ 31 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/endian.h> 37 #include <sys/errno.h> 38 #include <sys/malloc.h> 39 #include <sys/mbuf.h> 40 #include <sys/module.h> 41 #include <sys/uio.h> 42 43 #include <sys/mchain.h> 44 45 MODULE_VERSION(libmchain, 1); 46 47 #define MBERROR(format, ...) kprintf("%s(%d): "format, __func__ , \ 48 __LINE__ , ## __VA_ARGS__) 49 50 #define MBPANIC(format, ...) kprintf("%s(%d): "format, __func__ , \ 51 __LINE__ , ## __VA_ARGS__) 52 53 /* 54 * Various helper functions 55 */ 56 int 57 m_fixhdr(struct mbuf *m0) 58 { 59 struct mbuf *m = m0; 60 int len = 0; 61 62 while (m) { 63 len += m->m_len; 64 m = m->m_next; 65 } 66 m0->m_pkthdr.len = len; 67 return len; 68 } 69 70 int 71 mb_init(struct mbchain *mbp) 72 { 73 struct mbuf *m; 74 75 m = m_gethdr(M_WAITOK, MT_DATA); 76 if (m == NULL) 77 return ENOBUFS; 78 m->m_pkthdr.rcvif = NULL; 79 m->m_len = 0; 80 mb_initm(mbp, m); 81 return 0; 82 } 83 84 void 85 mb_initm(struct mbchain *mbp, struct mbuf *m) 86 { 87 bzero(mbp, sizeof(*mbp)); 88 mbp->mb_top = mbp->mb_cur = m; 89 mbp->mb_mleft = M_TRAILINGSPACE(m); 90 } 91 92 void 93 mb_done(struct mbchain *mbp) 94 { 95 if (mbp->mb_top) { 96 m_freem(mbp->mb_top); 97 mbp->mb_top = NULL; 98 } 99 } 100 101 struct mbuf * 102 mb_detach(struct mbchain *mbp) 103 { 104 struct mbuf *m; 105 106 m = mbp->mb_top; 107 mbp->mb_top = NULL; 108 return m; 109 } 110 111 int 112 mb_fixhdr(struct mbchain *mbp) 113 { 114 return mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top); 115 } 116 117 /* 118 * Check if object of size 'size' fit to the current position and 119 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s). 120 * Return pointer to the object placeholder or NULL if any error occured. 121 * Note: size should be <= MLEN 122 */ 123 caddr_t 124 mb_reserve(struct mbchain *mbp, int size) 125 { 126 struct mbuf *m, *mn; 127 caddr_t bpos; 128 129 if (size > MLEN) 130 panic("mb_reserve: size = %d", size); 131 m = mbp->mb_cur; 132 if (mbp->mb_mleft < size) { 133 mn = m_get(M_WAITOK, MT_DATA); 134 if (mn == NULL) 135 return NULL; 136 mbp->mb_cur = m->m_next = mn; 137 m = mn; 138 m->m_len = 0; 139 mbp->mb_mleft = M_TRAILINGSPACE(m); 140 } 141 mbp->mb_mleft -= size; 142 mbp->mb_count += size; 143 bpos = mtod(m, caddr_t) + m->m_len; 144 m->m_len += size; 145 return bpos; 146 } 147 148 int 149 mb_put_uint8(struct mbchain *mbp, u_int8_t x) 150 { 151 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 152 } 153 154 int 155 mb_put_uint16be(struct mbchain *mbp, u_int16_t x) 156 { 157 x = htobe16(x); 158 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 159 } 160 161 int 162 mb_put_uint16le(struct mbchain *mbp, u_int16_t x) 163 { 164 x = htole16(x); 165 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 166 } 167 168 int 169 mb_put_uint32be(struct mbchain *mbp, u_int32_t x) 170 { 171 x = htobe32(x); 172 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 173 } 174 175 int 176 mb_put_uint32le(struct mbchain *mbp, u_int32_t x) 177 { 178 x = htole32(x); 179 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 180 } 181 182 int 183 mb_put_int64be(struct mbchain *mbp, int64_t x) 184 { 185 x = htobe64(x); 186 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 187 } 188 189 int 190 mb_put_int64le(struct mbchain *mbp, int64_t x) 191 { 192 x = htole64(x); 193 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 194 } 195 196 int 197 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type) 198 { 199 struct mbuf *m; 200 caddr_t dst; 201 c_caddr_t src; 202 int error, mleft, count; 203 size_t cplen, srclen, dstlen; 204 205 m = mbp->mb_cur; 206 mleft = mbp->mb_mleft; 207 208 while (size > 0) { 209 if (mleft == 0) { 210 if (m->m_next == NULL) { 211 m->m_next = m_getc(size, M_WAITOK, MT_DATA); 212 if (m->m_next == NULL) 213 return ENOBUFS; 214 } 215 m = m->m_next; 216 mleft = M_TRAILINGSPACE(m); 217 continue; 218 } 219 cplen = mleft > size ? size : mleft; 220 srclen = dstlen = cplen; 221 dst = mtod(m, caddr_t) + m->m_len; 222 switch (type) { 223 case MB_MCUSTOM: 224 srclen = size; 225 dstlen = mleft; 226 error = mbp->mb_copy(mbp, source, dst, &srclen, &dstlen); 227 if (error) 228 return error; 229 break; 230 case MB_MINLINE: 231 for (src = source, count = cplen; count; count--) 232 *dst++ = *src++; 233 break; 234 case MB_MSYSTEM: 235 bcopy(source, dst, cplen); 236 break; 237 case MB_MUSER: 238 error = copyin(source, dst, cplen); 239 if (error) 240 return error; 241 break; 242 case MB_MZERO: 243 bzero(dst, cplen); 244 break; 245 } 246 size -= srclen; 247 source += srclen; 248 m->m_len += dstlen; 249 mleft -= dstlen; 250 mbp->mb_count += dstlen; 251 } 252 mbp->mb_cur = m; 253 mbp->mb_mleft = mleft; 254 return 0; 255 } 256 257 int 258 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m) 259 { 260 mbp->mb_cur->m_next = m; 261 while (m) { 262 mbp->mb_count += m->m_len; 263 if (m->m_next == NULL) 264 break; 265 m = m->m_next; 266 } 267 mbp->mb_mleft = M_TRAILINGSPACE(m); 268 mbp->mb_cur = m; 269 return 0; 270 } 271 272 /* 273 * copies a uio scatter/gather list to an mbuf chain. 274 */ 275 int 276 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size) 277 { 278 long left; 279 int mtype, error; 280 281 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 282 283 while (size > 0 && uiop->uio_resid) { 284 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 285 return EFBIG; 286 left = uiop->uio_iov->iov_len; 287 if (left == 0) { 288 uiop->uio_iov++; 289 uiop->uio_iovcnt--; 290 continue; 291 } 292 if (left > size) 293 left = size; 294 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype); 295 if (error) 296 return error; 297 uiop->uio_offset += left; 298 uiop->uio_resid -= left; 299 uiop->uio_iov->iov_base = 300 (char *)uiop->uio_iov->iov_base + left; 301 uiop->uio_iov->iov_len -= left; 302 size -= left; 303 } 304 return 0; 305 } 306 307 /* 308 * Routines for fetching data from an mbuf chain 309 */ 310 int 311 md_init(struct mdchain *mdp) 312 { 313 struct mbuf *m; 314 315 m = m_gethdr(M_WAITOK, MT_DATA); 316 if (m == NULL) 317 return ENOBUFS; 318 m->m_pkthdr.rcvif = NULL; 319 m->m_len = 0; 320 md_initm(mdp, m); 321 return 0; 322 } 323 324 void 325 md_initm(struct mdchain *mdp, struct mbuf *m) 326 { 327 bzero(mdp, sizeof(*mdp)); 328 mdp->md_top = mdp->md_cur = m; 329 mdp->md_pos = mtod(m, u_char*); 330 } 331 332 void 333 md_done(struct mdchain *mdp) 334 { 335 if (mdp->md_top) { 336 m_freem(mdp->md_top); 337 mdp->md_top = NULL; 338 } 339 } 340 341 /* 342 * Append a separate mbuf chain. It is caller responsibility to prevent 343 * multiple calls to fetch/record routines. 344 */ 345 void 346 md_append_record(struct mdchain *mdp, struct mbuf *top) 347 { 348 struct mbuf *m; 349 350 if (mdp->md_top == NULL) { 351 md_initm(mdp, top); 352 return; 353 } 354 m = mdp->md_top; 355 while (m->m_nextpkt) 356 m = m->m_nextpkt; 357 m->m_nextpkt = top; 358 top->m_nextpkt = NULL; 359 return; 360 } 361 362 /* 363 * Put next record in place of existing 364 */ 365 int 366 md_next_record(struct mdchain *mdp) 367 { 368 struct mbuf *m; 369 370 if (mdp->md_top == NULL) 371 return ENOENT; 372 m = mdp->md_top->m_nextpkt; 373 md_done(mdp); 374 if (m == NULL) 375 return ENOENT; 376 md_initm(mdp, m); 377 return 0; 378 } 379 380 int 381 md_get_uint8(struct mdchain *mdp, u_int8_t *x) 382 { 383 return md_get_mem(mdp, x, 1, MB_MINLINE); 384 } 385 386 int 387 md_get_uint16(struct mdchain *mdp, u_int16_t *x) 388 { 389 return md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE); 390 } 391 392 int 393 md_get_uint16le(struct mdchain *mdp, u_int16_t *x) 394 { 395 u_int16_t v; 396 int error = md_get_uint16(mdp, &v); 397 398 if (x != NULL) 399 *x = le16toh(v); 400 return error; 401 } 402 403 int 404 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) { 405 u_int16_t v; 406 int error = md_get_uint16(mdp, &v); 407 408 if (x != NULL) 409 *x = be16toh(v); 410 return error; 411 } 412 413 int 414 md_get_uint32(struct mdchain *mdp, u_int32_t *x) 415 { 416 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE); 417 } 418 419 int 420 md_get_uint32be(struct mdchain *mdp, u_int32_t *x) 421 { 422 u_int32_t v; 423 int error; 424 425 error = md_get_uint32(mdp, &v); 426 if (x != NULL) 427 *x = be32toh(v); 428 return error; 429 } 430 431 int 432 md_get_uint32le(struct mdchain *mdp, u_int32_t *x) 433 { 434 u_int32_t v; 435 int error; 436 437 error = md_get_uint32(mdp, &v); 438 if (x != NULL) 439 *x = le32toh(v); 440 return error; 441 } 442 443 int 444 md_get_int64(struct mdchain *mdp, int64_t *x) 445 { 446 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE); 447 } 448 449 int 450 md_get_int64be(struct mdchain *mdp, int64_t *x) 451 { 452 int64_t v; 453 int error; 454 455 error = md_get_int64(mdp, &v); 456 if (x != NULL) 457 *x = be64toh(v); 458 return error; 459 } 460 461 int 462 md_get_int64le(struct mdchain *mdp, int64_t *x) 463 { 464 int64_t v; 465 int error; 466 467 error = md_get_int64(mdp, &v); 468 if (x != NULL) 469 *x = le64toh(v); 470 return error; 471 } 472 473 int 474 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type) 475 { 476 struct mbuf *m = mdp->md_cur; 477 int error; 478 u_int count; 479 u_char *s; 480 481 while (size > 0) { 482 if (m == NULL) { 483 MBERROR("incomplete copy\n"); 484 return EBADRPC; 485 } 486 s = mdp->md_pos; 487 count = mtod(m, u_char*) + m->m_len - s; 488 if (count == 0) { 489 mdp->md_cur = m = m->m_next; 490 if (m) 491 s = mdp->md_pos = mtod(m, caddr_t); 492 continue; 493 } 494 if (count > size) 495 count = size; 496 size -= count; 497 mdp->md_pos += count; 498 if (target == NULL) 499 continue; 500 switch (type) { 501 case MB_MUSER: 502 error = copyout(s, target, count); 503 if (error) 504 return error; 505 break; 506 case MB_MSYSTEM: 507 bcopy(s, target, count); 508 break; 509 case MB_MINLINE: 510 while (count--) 511 *target++ = *s++; 512 continue; 513 } 514 target += count; 515 } 516 return 0; 517 } 518 519 int 520 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret) 521 { 522 struct mbuf *m = mdp->md_cur, *rm; 523 524 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, M_WAITOK); 525 if (rm == NULL) 526 return EBADRPC; 527 md_get_mem(mdp, NULL, size, MB_MZERO); 528 *ret = rm; 529 return 0; 530 } 531 532 int 533 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size) 534 { 535 char *uiocp; 536 long left; 537 int mtype, error; 538 539 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 540 while (size > 0 && uiop->uio_resid) { 541 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 542 return EFBIG; 543 left = uiop->uio_iov->iov_len; 544 if (left == 0) { 545 uiop->uio_iov++; 546 uiop->uio_iovcnt--; 547 continue; 548 } 549 uiocp = uiop->uio_iov->iov_base; 550 if (left > size) 551 left = size; 552 error = md_get_mem(mdp, uiocp, left, mtype); 553 if (error) 554 return error; 555 uiop->uio_offset += left; 556 uiop->uio_resid -= left; 557 uiop->uio_iov->iov_base = 558 (char *)uiop->uio_iov->iov_base + left; 559 uiop->uio_iov->iov_len -= left; 560 size -= left; 561 } 562 return 0; 563 } 564