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 * $DragonFly: src/sys/kern/libmchain/subr_mchain.c,v 1.6 2007/10/20 09:38:01 sephe Exp $ 34 */ 35 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/errno.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/module.h> 44 #include <sys/uio.h> 45 46 #include <sys/mchain.h> 47 48 MODULE_VERSION(libmchain, 1); 49 50 #define MBERROR(format, args...) kprintf("%s(%d): "format, __func__ , \ 51 __LINE__ ,## args) 52 53 #define MBPANIC(format, args...) kprintf("%s(%d): "format, __func__ , \ 54 __LINE__ ,## args) 55 56 /* 57 * Various helper functions 58 */ 59 int 60 m_fixhdr(struct mbuf *m0) 61 { 62 struct mbuf *m = m0; 63 int len = 0; 64 65 while (m) { 66 len += m->m_len; 67 m = m->m_next; 68 } 69 m0->m_pkthdr.len = len; 70 return len; 71 } 72 73 int 74 mb_init(struct mbchain *mbp) 75 { 76 struct mbuf *m; 77 78 m = m_gethdr(MB_WAIT, MT_DATA); 79 if (m == NULL) 80 return ENOBUFS; 81 m->m_pkthdr.rcvif = NULL; 82 m->m_len = 0; 83 mb_initm(mbp, m); 84 return 0; 85 } 86 87 void 88 mb_initm(struct mbchain *mbp, struct mbuf *m) 89 { 90 bzero(mbp, sizeof(*mbp)); 91 mbp->mb_top = mbp->mb_cur = m; 92 mbp->mb_mleft = M_TRAILINGSPACE(m); 93 } 94 95 void 96 mb_done(struct mbchain *mbp) 97 { 98 if (mbp->mb_top) { 99 m_freem(mbp->mb_top); 100 mbp->mb_top = NULL; 101 } 102 } 103 104 struct mbuf * 105 mb_detach(struct mbchain *mbp) 106 { 107 struct mbuf *m; 108 109 m = mbp->mb_top; 110 mbp->mb_top = NULL; 111 return m; 112 } 113 114 int 115 mb_fixhdr(struct mbchain *mbp) 116 { 117 return mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top); 118 } 119 120 /* 121 * Check if object of size 'size' fit to the current position and 122 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s). 123 * Return pointer to the object placeholder or NULL if any error occured. 124 * Note: size should be <= MLEN 125 */ 126 caddr_t 127 mb_reserve(struct mbchain *mbp, int size) 128 { 129 struct mbuf *m, *mn; 130 caddr_t bpos; 131 132 if (size > MLEN) 133 panic("mb_reserve: size = %d\n", size); 134 m = mbp->mb_cur; 135 if (mbp->mb_mleft < size) { 136 mn = m_get(MB_WAIT, MT_DATA); 137 if (mn == NULL) 138 return NULL; 139 mbp->mb_cur = m->m_next = mn; 140 m = mn; 141 m->m_len = 0; 142 mbp->mb_mleft = M_TRAILINGSPACE(m); 143 } 144 mbp->mb_mleft -= size; 145 mbp->mb_count += size; 146 bpos = mtod(m, caddr_t) + m->m_len; 147 m->m_len += size; 148 return bpos; 149 } 150 151 int 152 mb_put_uint8(struct mbchain *mbp, u_int8_t x) 153 { 154 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 155 } 156 157 int 158 mb_put_uint16be(struct mbchain *mbp, u_int16_t x) 159 { 160 x = htobes(x); 161 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 162 } 163 164 int 165 mb_put_uint16le(struct mbchain *mbp, u_int16_t x) 166 { 167 x = htoles(x); 168 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 169 } 170 171 int 172 mb_put_uint32be(struct mbchain *mbp, u_int32_t x) 173 { 174 x = htobel(x); 175 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 176 } 177 178 int 179 mb_put_uint32le(struct mbchain *mbp, u_int32_t x) 180 { 181 x = htolel(x); 182 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 183 } 184 185 int 186 mb_put_int64be(struct mbchain *mbp, int64_t x) 187 { 188 x = htobeq(x); 189 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 190 } 191 192 int 193 mb_put_int64le(struct mbchain *mbp, int64_t x) 194 { 195 x = htoleq(x); 196 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM); 197 } 198 199 int 200 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type) 201 { 202 struct mbuf *m; 203 caddr_t dst; 204 c_caddr_t src; 205 int error, mleft, count; 206 size_t cplen; 207 208 m = mbp->mb_cur; 209 mleft = mbp->mb_mleft; 210 211 while (size > 0) { 212 if (mleft == 0) { 213 if (m->m_next == NULL) { 214 m->m_next = m_getc(size, MB_WAIT, MT_DATA); 215 if (m == NULL) 216 return ENOBUFS; 217 } 218 m = m->m_next; 219 mleft = M_TRAILINGSPACE(m); 220 continue; 221 } 222 cplen = mleft > size ? size : mleft; 223 dst = mtod(m, caddr_t) + m->m_len; 224 switch (type) { 225 case MB_MCUSTOM: 226 error = mbp->mb_copy(mbp, source, dst, cplen); 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 -= cplen; 247 source += cplen; 248 m->m_len += cplen; 249 mleft -= cplen; 250 mbp->mb_count += cplen; 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 = (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 *x = letohs(v); 398 return error; 399 } 400 401 int 402 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) { 403 u_int16_t v; 404 int error = md_get_uint16(mdp, &v); 405 406 *x = betohs(v); 407 return error; 408 } 409 410 int 411 md_get_uint32(struct mdchain *mdp, u_int32_t *x) 412 { 413 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE); 414 } 415 416 int 417 md_get_uint32be(struct mdchain *mdp, u_int32_t *x) 418 { 419 u_int32_t v; 420 int error; 421 422 error = md_get_uint32(mdp, &v); 423 *x = betohl(v); 424 return error; 425 } 426 427 int 428 md_get_uint32le(struct mdchain *mdp, u_int32_t *x) 429 { 430 u_int32_t v; 431 int error; 432 433 error = md_get_uint32(mdp, &v); 434 *x = letohl(v); 435 return error; 436 } 437 438 int 439 md_get_int64(struct mdchain *mdp, int64_t *x) 440 { 441 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE); 442 } 443 444 int 445 md_get_int64be(struct mdchain *mdp, int64_t *x) 446 { 447 int64_t v; 448 int error; 449 450 error = md_get_int64(mdp, &v); 451 *x = betohq(v); 452 return error; 453 } 454 455 int 456 md_get_int64le(struct mdchain *mdp, int64_t *x) 457 { 458 int64_t v; 459 int error; 460 461 error = md_get_int64(mdp, &v); 462 *x = letohq(v); 463 return error; 464 } 465 466 int 467 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type) 468 { 469 struct mbuf *m = mdp->md_cur; 470 int error; 471 u_int count; 472 u_char *s; 473 474 while (size > 0) { 475 if (m == NULL) { 476 MBERROR("incomplete copy\n"); 477 return EBADRPC; 478 } 479 s = mdp->md_pos; 480 count = mtod(m, u_char*) + m->m_len - s; 481 if (count == 0) { 482 mdp->md_cur = m = m->m_next; 483 if (m) 484 s = mdp->md_pos = mtod(m, caddr_t); 485 continue; 486 } 487 if (count > size) 488 count = size; 489 size -= count; 490 mdp->md_pos += count; 491 if (target == NULL) 492 continue; 493 switch (type) { 494 case MB_MUSER: 495 error = copyout(s, target, count); 496 if (error) 497 return error; 498 break; 499 case MB_MSYSTEM: 500 bcopy(s, target, count); 501 break; 502 case MB_MINLINE: 503 while (count--) 504 *target++ = *s++; 505 continue; 506 } 507 target += count; 508 } 509 return 0; 510 } 511 512 int 513 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret) 514 { 515 struct mbuf *m = mdp->md_cur, *rm; 516 517 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, MB_WAIT); 518 if (rm == NULL) 519 return EBADRPC; 520 md_get_mem(mdp, NULL, size, MB_MZERO); 521 *ret = rm; 522 return 0; 523 } 524 525 int 526 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size) 527 { 528 char *uiocp; 529 long left; 530 int mtype, error; 531 532 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 533 while (size > 0 && uiop->uio_resid) { 534 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 535 return EFBIG; 536 left = uiop->uio_iov->iov_len; 537 if (left == 0) { 538 uiop->uio_iov++; 539 uiop->uio_iovcnt--; 540 continue; 541 } 542 uiocp = uiop->uio_iov->iov_base; 543 if (left > size) 544 left = size; 545 error = md_get_mem(mdp, uiocp, left, mtype); 546 if (error) 547 return error; 548 uiop->uio_offset += left; 549 uiop->uio_resid -= left; 550 uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + left; 551 uiop->uio_iov->iov_len -= left; 552 size -= left; 553 } 554 return 0; 555 } 556