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