1 /*-
2 * Copyright (c) 2007-2008 Kip Macy <kmacy@freebsd.org>
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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/lock.h>
34 #include <sys/malloc.h>
35 #include <sys/mbuf.h>
36 #include <sys/ktr.h>
37
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40
41 #include <machine/bus.h>
42
43 #include <cxgb_include.h>
44 #include <sys/mvec.h>
45
46 #ifdef INVARIANTS
47 #define M_SANITY m_sanity
48 #else
49 #define M_SANITY(a, b)
50 #endif
51
52 int
busdma_map_sg_collapse(bus_dma_tag_t tag,bus_dmamap_t map,struct mbuf ** m,bus_dma_segment_t * segs,int * nsegs)53 busdma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map,
54 struct mbuf **m, bus_dma_segment_t *segs, int *nsegs)
55 {
56 struct mbuf *n = *m;
57 int seg_count, defragged = 0, err = 0;
58 bus_dma_segment_t *psegs;
59
60 KASSERT(n->m_pkthdr.len, ("packet has zero header len"));
61 if (n->m_pkthdr.len <= PIO_LEN)
62 return (0);
63 retry:
64 psegs = segs;
65 seg_count = 0;
66 if (n->m_next == NULL) {
67 busdma_map_mbuf_fast(tag, map, n, segs);
68 *nsegs = 1;
69 return (0);
70 }
71 #if defined(__i386__) || defined(__amd64__)
72 while (n && seg_count < TX_MAX_SEGS) {
73 /*
74 * firmware doesn't like empty segments
75 */
76 if (__predict_true(n->m_len != 0)) {
77 seg_count++;
78 busdma_map_mbuf_fast(tag, map, n, psegs);
79 psegs++;
80 }
81 n = n->m_next;
82 }
83 #else
84 err = bus_dmamap_load_mbuf_sg(tag, map, *m, segs, &seg_count, 0);
85 #endif
86 if (seg_count == 0) {
87 if (cxgb_debug)
88 printf("empty segment chain\n");
89 err = EFBIG;
90 goto err_out;
91 } else if (err == EFBIG || seg_count >= TX_MAX_SEGS) {
92 if (cxgb_debug)
93 printf("mbuf chain too long: %d max allowed %d\n",
94 seg_count, TX_MAX_SEGS);
95 if (!defragged) {
96 n = m_defrag(*m, M_NOWAIT);
97 if (n == NULL) {
98 err = ENOBUFS;
99 goto err_out;
100 }
101 *m = n;
102 defragged = 1;
103 goto retry;
104 }
105 err = EFBIG;
106 goto err_out;
107 }
108
109 *nsegs = seg_count;
110 err_out:
111 return (err);
112 }
113
114 void
busdma_map_sg_vec(bus_dma_tag_t tag,bus_dmamap_t map,struct mbuf * m,bus_dma_segment_t * segs,int * nsegs)115 busdma_map_sg_vec(bus_dma_tag_t tag, bus_dmamap_t map,
116 struct mbuf *m, bus_dma_segment_t *segs, int *nsegs)
117 {
118
119 for (*nsegs = 0; m != NULL ; segs++, *nsegs += 1, m = m->m_nextpkt)
120 busdma_map_mbuf_fast(tag, map, m, segs);
121 }
122
123