2 * Copyright (c) 2000, 2001 Boris Popov
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
29 * $FreeBSD: src/sys/kern/subr_mchain.c,v 1.2.2.2 2002/04/13 12:46:40 bp Exp $
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>
39 #include <sys/module.h>
42 #include <sys/mchain.h>
44 MODULE_VERSION(libmchain, 1);
46 #define MBERROR(format, ...) kprintf("%s(%d): "format, __func__ , \
47 __LINE__ , ## __VA_ARGS__)
49 #define MBPANIC(format, ...) kprintf("%s(%d): "format, __func__ , \
50 __LINE__ , ## __VA_ARGS__)
53 * Various helper functions
56 m_fixhdr(struct mbuf *m0)
65 m0->m_pkthdr.len = len;
70 mb_init(struct mbchain *mbp)
74 m = m_gethdr(MB_WAIT, MT_DATA);
77 m->m_pkthdr.rcvif = NULL;
84 mb_initm(struct mbchain *mbp, struct mbuf *m)
86 bzero(mbp, sizeof(*mbp));
87 mbp->mb_top = mbp->mb_cur = m;
88 mbp->mb_mleft = M_TRAILINGSPACE(m);
92 mb_done(struct mbchain *mbp)
101 mb_detach(struct mbchain *mbp)
111 mb_fixhdr(struct mbchain *mbp)
113 return mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top);
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
123 mb_reserve(struct mbchain *mbp, int size)
129 panic("mb_reserve: size = %d", size);
131 if (mbp->mb_mleft < size) {
132 mn = m_get(MB_WAIT, MT_DATA);
135 mbp->mb_cur = m->m_next = mn;
138 mbp->mb_mleft = M_TRAILINGSPACE(m);
140 mbp->mb_mleft -= size;
141 mbp->mb_count += size;
142 bpos = mtod(m, caddr_t) + m->m_len;
148 mb_put_uint8(struct mbchain *mbp, u_int8_t x)
150 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
154 mb_put_uint16be(struct mbchain *mbp, u_int16_t x)
157 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
161 mb_put_uint16le(struct mbchain *mbp, u_int16_t x)
164 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
168 mb_put_uint32be(struct mbchain *mbp, u_int32_t x)
171 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
175 mb_put_uint32le(struct mbchain *mbp, u_int32_t x)
178 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
182 mb_put_int64be(struct mbchain *mbp, int64_t x)
185 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
189 mb_put_int64le(struct mbchain *mbp, int64_t x)
192 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
196 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type)
201 int error, mleft, count;
202 size_t cplen, srclen, dstlen;
205 mleft = mbp->mb_mleft;
209 if (m->m_next == NULL) {
210 m->m_next = m_getc(size, MB_WAIT, MT_DATA);
211 if (m->m_next == NULL)
215 mleft = M_TRAILINGSPACE(m);
218 cplen = mleft > size ? size : mleft;
219 srclen = dstlen = cplen;
220 dst = mtod(m, caddr_t) + m->m_len;
225 error = mbp->mb_copy(mbp, source, dst, &srclen, &dstlen);
230 for (src = source, count = cplen; count; count--)
234 bcopy(source, dst, cplen);
237 error = copyin(source, dst, cplen);
249 mbp->mb_count += dstlen;
252 mbp->mb_mleft = mleft;
257 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m)
259 mbp->mb_cur->m_next = m;
261 mbp->mb_count += m->m_len;
262 if (m->m_next == NULL)
266 mbp->mb_mleft = M_TRAILINGSPACE(m);
272 * copies a uio scatter/gather list to an mbuf chain.
275 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size)
280 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER;
282 while (size > 0 && uiop->uio_resid) {
283 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
285 left = uiop->uio_iov->iov_len;
293 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype);
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;
307 * Routines for fetching data from an mbuf chain
310 md_init(struct mdchain *mdp)
314 m = m_gethdr(MB_WAIT, MT_DATA);
317 m->m_pkthdr.rcvif = NULL;
324 md_initm(struct mdchain *mdp, struct mbuf *m)
326 bzero(mdp, sizeof(*mdp));
327 mdp->md_top = mdp->md_cur = m;
328 mdp->md_pos = mtod(m, u_char*);
332 md_done(struct mdchain *mdp)
335 m_freem(mdp->md_top);
341 * Append a separate mbuf chain. It is caller responsibility to prevent
342 * multiple calls to fetch/record routines.
345 md_append_record(struct mdchain *mdp, struct mbuf *top)
349 if (mdp->md_top == NULL) {
357 top->m_nextpkt = NULL;
362 * Put next record in place of existing
365 md_next_record(struct mdchain *mdp)
369 if (mdp->md_top == NULL)
371 m = mdp->md_top->m_nextpkt;
380 md_get_uint8(struct mdchain *mdp, u_int8_t *x)
382 return md_get_mem(mdp, x, 1, MB_MINLINE);
386 md_get_uint16(struct mdchain *mdp, u_int16_t *x)
388 return md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE);
392 md_get_uint16le(struct mdchain *mdp, u_int16_t *x)
395 int error = md_get_uint16(mdp, &v);
403 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) {
405 int error = md_get_uint16(mdp, &v);
413 md_get_uint32(struct mdchain *mdp, u_int32_t *x)
415 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE);
419 md_get_uint32be(struct mdchain *mdp, u_int32_t *x)
424 error = md_get_uint32(mdp, &v);
431 md_get_uint32le(struct mdchain *mdp, u_int32_t *x)
436 error = md_get_uint32(mdp, &v);
443 md_get_int64(struct mdchain *mdp, int64_t *x)
445 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE);
449 md_get_int64be(struct mdchain *mdp, int64_t *x)
454 error = md_get_int64(mdp, &v);
461 md_get_int64le(struct mdchain *mdp, int64_t *x)
466 error = md_get_int64(mdp, &v);
473 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type)
475 struct mbuf *m = mdp->md_cur;
482 MBERROR("incomplete copy\n");
486 count = mtod(m, u_char*) + m->m_len - s;
488 mdp->md_cur = m = m->m_next;
490 s = mdp->md_pos = mtod(m, caddr_t);
496 mdp->md_pos += count;
501 error = copyout(s, target, count);
506 bcopy(s, target, count);
519 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret)
521 struct mbuf *m = mdp->md_cur, *rm;
523 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, MB_WAIT);
526 md_get_mem(mdp, NULL, size, MB_MZERO);
532 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size)
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)
542 left = uiop->uio_iov->iov_len;
548 uiocp = uiop->uio_iov->iov_base;
551 error = md_get_mem(mdp, uiocp, left, mtype);
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;