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 cplen, error, mleft, count; 206 207 m = mbp->mb_cur; 208 mleft = mbp->mb_mleft; 209 210 while (size > 0) { 211 if (mleft == 0) { 212 if (m->m_next == NULL) { 213 m->m_next = m_getc(size, MB_WAIT, MT_DATA); 214 if (m == NULL) 215 return ENOBUFS; 216 } 217 m = m->m_next; 218 mleft = M_TRAILINGSPACE(m); 219 continue; 220 } 221 cplen = mleft > size ? size : mleft; 222 dst = mtod(m, caddr_t) + m->m_len; 223 switch (type) { 224 case MB_MCUSTOM: 225 error = mbp->mb_copy(mbp, source, dst, cplen); 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 -= cplen; 246 source += cplen; 247 m->m_len += cplen; 248 mleft -= cplen; 249 mbp->mb_count += cplen; 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 += left; 299 uiop->uio_iov->iov_len -= left; 300 size -= left; 301 } 302 return 0; 303 } 304 305 /* 306 * Routines for fetching data from an mbuf chain 307 */ 308 int 309 md_init(struct mdchain *mdp) 310 { 311 struct mbuf *m; 312 313 m = m_gethdr(MB_WAIT, MT_DATA); 314 if (m == NULL) 315 return ENOBUFS; 316 m->m_pkthdr.rcvif = NULL; 317 m->m_len = 0; 318 md_initm(mdp, m); 319 return 0; 320 } 321 322 void 323 md_initm(struct mdchain *mdp, struct mbuf *m) 324 { 325 bzero(mdp, sizeof(*mdp)); 326 mdp->md_top = mdp->md_cur = m; 327 mdp->md_pos = mtod(m, u_char*); 328 } 329 330 void 331 md_done(struct mdchain *mdp) 332 { 333 if (mdp->md_top) { 334 m_freem(mdp->md_top); 335 mdp->md_top = NULL; 336 } 337 } 338 339 /* 340 * Append a separate mbuf chain. It is caller responsibility to prevent 341 * multiple calls to fetch/record routines. 342 */ 343 void 344 md_append_record(struct mdchain *mdp, struct mbuf *top) 345 { 346 struct mbuf *m; 347 348 if (mdp->md_top == NULL) { 349 md_initm(mdp, top); 350 return; 351 } 352 m = mdp->md_top; 353 while (m->m_nextpkt) 354 m = m->m_nextpkt; 355 m->m_nextpkt = top; 356 top->m_nextpkt = NULL; 357 return; 358 } 359 360 /* 361 * Put next record in place of existing 362 */ 363 int 364 md_next_record(struct mdchain *mdp) 365 { 366 struct mbuf *m; 367 368 if (mdp->md_top == NULL) 369 return ENOENT; 370 m = mdp->md_top->m_nextpkt; 371 md_done(mdp); 372 if (m == NULL) 373 return ENOENT; 374 md_initm(mdp, m); 375 return 0; 376 } 377 378 int 379 md_get_uint8(struct mdchain *mdp, u_int8_t *x) 380 { 381 return md_get_mem(mdp, x, 1, MB_MINLINE); 382 } 383 384 int 385 md_get_uint16(struct mdchain *mdp, u_int16_t *x) 386 { 387 return md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE); 388 } 389 390 int 391 md_get_uint16le(struct mdchain *mdp, u_int16_t *x) 392 { 393 u_int16_t v; 394 int error = md_get_uint16(mdp, &v); 395 396 *x = letohs(v); 397 return error; 398 } 399 400 int 401 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) { 402 u_int16_t v; 403 int error = md_get_uint16(mdp, &v); 404 405 *x = betohs(v); 406 return error; 407 } 408 409 int 410 md_get_uint32(struct mdchain *mdp, u_int32_t *x) 411 { 412 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE); 413 } 414 415 int 416 md_get_uint32be(struct mdchain *mdp, u_int32_t *x) 417 { 418 u_int32_t v; 419 int error; 420 421 error = md_get_uint32(mdp, &v); 422 *x = betohl(v); 423 return error; 424 } 425 426 int 427 md_get_uint32le(struct mdchain *mdp, u_int32_t *x) 428 { 429 u_int32_t v; 430 int error; 431 432 error = md_get_uint32(mdp, &v); 433 *x = letohl(v); 434 return error; 435 } 436 437 int 438 md_get_int64(struct mdchain *mdp, int64_t *x) 439 { 440 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE); 441 } 442 443 int 444 md_get_int64be(struct mdchain *mdp, int64_t *x) 445 { 446 int64_t v; 447 int error; 448 449 error = md_get_int64(mdp, &v); 450 *x = betohq(v); 451 return error; 452 } 453 454 int 455 md_get_int64le(struct mdchain *mdp, int64_t *x) 456 { 457 int64_t v; 458 int error; 459 460 error = md_get_int64(mdp, &v); 461 *x = letohq(v); 462 return error; 463 } 464 465 int 466 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type) 467 { 468 struct mbuf *m = mdp->md_cur; 469 int error; 470 u_int count; 471 u_char *s; 472 473 while (size > 0) { 474 if (m == NULL) { 475 MBERROR("incomplete copy\n"); 476 return EBADRPC; 477 } 478 s = mdp->md_pos; 479 count = mtod(m, u_char*) + m->m_len - s; 480 if (count == 0) { 481 mdp->md_cur = m = m->m_next; 482 if (m) 483 s = mdp->md_pos = mtod(m, caddr_t); 484 continue; 485 } 486 if (count > size) 487 count = size; 488 size -= count; 489 mdp->md_pos += count; 490 if (target == NULL) 491 continue; 492 switch (type) { 493 case MB_MUSER: 494 error = copyout(s, target, count); 495 if (error) 496 return error; 497 break; 498 case MB_MSYSTEM: 499 bcopy(s, target, count); 500 break; 501 case MB_MINLINE: 502 while (count--) 503 *target++ = *s++; 504 continue; 505 } 506 target += count; 507 } 508 return 0; 509 } 510 511 int 512 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret) 513 { 514 struct mbuf *m = mdp->md_cur, *rm; 515 516 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, MB_WAIT); 517 if (rm == NULL) 518 return EBADRPC; 519 md_get_mem(mdp, NULL, size, MB_MZERO); 520 *ret = rm; 521 return 0; 522 } 523 524 int 525 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size) 526 { 527 char *uiocp; 528 long left; 529 int mtype, error; 530 531 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 532 while (size > 0 && uiop->uio_resid) { 533 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 534 return EFBIG; 535 left = uiop->uio_iov->iov_len; 536 if (left == 0) { 537 uiop->uio_iov++; 538 uiop->uio_iovcnt--; 539 continue; 540 } 541 uiocp = uiop->uio_iov->iov_base; 542 if (left > size) 543 left = size; 544 error = md_get_mem(mdp, uiocp, left, mtype); 545 if (error) 546 return error; 547 uiop->uio_offset += left; 548 uiop->uio_resid -= left; 549 uiop->uio_iov->iov_base += left; 550 uiop->uio_iov->iov_len -= left; 551 size -= left; 552 } 553 return 0; 554 } 555