1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2007-2008 Kip Macy <kmacy@freebsd.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/lock.h>
33 #include <sys/malloc.h>
34 #include <sys/mbuf.h>
35 #include <sys/ktr.h>
36
37 #include <vm/vm.h>
38 #include <vm/pmap.h>
39
40 #include <machine/bus.h>
41
42 #include <cxgb_include.h>
43 #include <sys/mvec.h>
44
45 #ifdef INVARIANTS
46 #define M_SANITY m_sanity
47 #else
48 #define M_SANITY(a, b)
49 #endif
50
51 int
busdma_map_sg_collapse(bus_dma_tag_t tag,bus_dmamap_t map,struct mbuf ** m,bus_dma_segment_t * segs,int * nsegs)52 busdma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map,
53 struct mbuf **m, bus_dma_segment_t *segs, int *nsegs)
54 {
55 struct mbuf *n = *m;
56 int seg_count, defragged = 0, err = 0;
57
58 KASSERT(n->m_pkthdr.len, ("packet has zero header len"));
59 if (n->m_pkthdr.len <= PIO_LEN)
60 return (0);
61 retry:
62 seg_count = 0;
63 err = bus_dmamap_load_mbuf_sg(tag, map, *m, segs, &seg_count, 0);
64 if (seg_count == 0) {
65 if (cxgb_debug)
66 printf("empty segment chain\n");
67 err = EFBIG;
68 goto err_out;
69 } else if (err == EFBIG || seg_count >= TX_MAX_SEGS) {
70 if (cxgb_debug)
71 printf("mbuf chain too long: %d max allowed %d\n",
72 seg_count, TX_MAX_SEGS);
73 if (!defragged) {
74 n = m_defrag(*m, M_NOWAIT);
75 if (n == NULL) {
76 err = ENOBUFS;
77 goto err_out;
78 }
79 *m = n;
80 defragged = 1;
81 goto retry;
82 }
83 err = EFBIG;
84 goto err_out;
85 }
86
87 *nsegs = seg_count;
88 err_out:
89 return (err);
90 }
91
92 void
busdma_map_sg_vec(bus_dma_tag_t tag,bus_dmamap_t map,struct mbuf * m,bus_dma_segment_t * segs,int * nsegs)93 busdma_map_sg_vec(bus_dma_tag_t tag, bus_dmamap_t map,
94 struct mbuf *m, bus_dma_segment_t *segs, int *nsegs)
95 {
96 int n = 0;
97
98 for (*nsegs = 0; m != NULL; segs += n, *nsegs += n, m = m->m_nextpkt)
99 bus_dmamap_load_mbuf_sg(tag, map, m, segs, &n, 0);
100 }
101
102