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 52int 53busdma_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); 63retry: 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; 110err_out: 111 return (err); 112} 113 114void 115busdma_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