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/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kernel.h> 35 #include <sys/lock.h> 36 #include <sys/malloc.h> 37 #include <sys/mbuf.h> 38 #include <sys/ktr.h> 39 40 #include <vm/vm.h> 41 #include <vm/pmap.h> 42 43 #include <machine/bus.h> 44 45 #include <cxgb_include.h> 46 #include <sys/mvec.h> 47 48 #ifdef INVARIANTS 49 #define M_SANITY m_sanity 50 #else 51 #define M_SANITY(a, b) 52 #endif 53 54 int 55 busdma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map, 56 struct mbuf **m, bus_dma_segment_t *segs, int *nsegs) 57 { 58 struct mbuf *n = *m; 59 int seg_count, defragged = 0, err = 0; 60 61 KASSERT(n->m_pkthdr.len, ("packet has zero header len")); 62 if (n->m_pkthdr.len <= PIO_LEN) 63 return (0); 64 retry: 65 seg_count = 0; 66 err = bus_dmamap_load_mbuf_sg(tag, map, *m, segs, &seg_count, 0); 67 if (seg_count == 0) { 68 if (cxgb_debug) 69 printf("empty segment chain\n"); 70 err = EFBIG; 71 goto err_out; 72 } else if (err == EFBIG || seg_count >= TX_MAX_SEGS) { 73 if (cxgb_debug) 74 printf("mbuf chain too long: %d max allowed %d\n", 75 seg_count, TX_MAX_SEGS); 76 if (!defragged) { 77 n = m_defrag(*m, M_NOWAIT); 78 if (n == NULL) { 79 err = ENOBUFS; 80 goto err_out; 81 } 82 *m = n; 83 defragged = 1; 84 goto retry; 85 } 86 err = EFBIG; 87 goto err_out; 88 } 89 90 *nsegs = seg_count; 91 err_out: 92 return (err); 93 } 94 95 void 96 busdma_map_sg_vec(bus_dma_tag_t tag, bus_dmamap_t map, 97 struct mbuf *m, bus_dma_segment_t *segs, int *nsegs) 98 { 99 int n = 0; 100 101 for (*nsegs = 0; m != NULL; segs += n, *nsegs += n, m = m->m_nextpkt) 102 bus_dmamap_load_mbuf_sg(tag, map, m, segs, &n, 0); 103 } 104 105