1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. 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 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/socket.h> 34 35 #ifndef ALTQ 36 #define ALTQ /* Needed for ifq.h prototypes only. */ 37 #endif 38 39 #include <net/if.h> 40 #include <net/if_var.h> 41 #include <net/if_private.h> 42 #include <net/ifq.h> 43 44 int 45 drbr_enqueue(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m) 46 { 47 int error = 0; 48 49 if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 50 IFQ_ENQUEUE(&ifp->if_snd, m, error); 51 if (error) 52 if_inc_counter((ifp), IFCOUNTER_OQDROPS, 1); 53 return (error); 54 } 55 error = buf_ring_enqueue(br, m); 56 if (error) 57 m_freem(m); 58 59 return (error); 60 } 61 62 void 63 drbr_putback(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m_new) 64 { 65 /* 66 * The top of the list needs to be swapped 67 * for this one. 68 */ 69 if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) { 70 /* 71 * Peek in altq case dequeued it 72 * so put it back. 73 */ 74 IFQ_DRV_PREPEND(&ifp->if_snd, m_new); 75 return; 76 } 77 buf_ring_putback_sc(br, m_new); 78 } 79 80 struct mbuf * 81 drbr_peek(struct ifnet *ifp, struct buf_ring *br) 82 { 83 struct mbuf *m; 84 if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) { 85 /* 86 * Pull it off like a dequeue 87 * since drbr_advance() does nothing 88 * for altq and drbr_putback() will 89 * use the old prepend function. 90 */ 91 IFQ_DEQUEUE(&ifp->if_snd, m); 92 return (m); 93 } 94 return ((struct mbuf *)buf_ring_peek_clear_sc(br)); 95 } 96 97 void 98 drbr_flush(struct ifnet *ifp, struct buf_ring *br) 99 { 100 struct mbuf *m; 101 102 if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) 103 IFQ_PURGE(&ifp->if_snd); 104 while ((m = (struct mbuf *)buf_ring_dequeue_sc(br)) != NULL) 105 m_freem(m); 106 } 107 108 struct mbuf * 109 drbr_dequeue(struct ifnet *ifp, struct buf_ring *br) 110 { 111 struct mbuf *m; 112 113 if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) { 114 IFQ_DEQUEUE(&ifp->if_snd, m); 115 return (m); 116 } 117 return ((struct mbuf *)buf_ring_dequeue_sc(br)); 118 } 119 120 void 121 drbr_advance(struct ifnet *ifp, struct buf_ring *br) 122 { 123 /* Nothing to do here since peek dequeues in altq case */ 124 if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) 125 return; 126 return (buf_ring_advance_sc(br)); 127 } 128 129 struct mbuf * 130 drbr_dequeue_cond(struct ifnet *ifp, struct buf_ring *br, 131 int (*func) (struct mbuf *, void *), void *arg) 132 { 133 struct mbuf *m; 134 if (ALTQ_IS_ENABLED(&ifp->if_snd)) { 135 IFQ_LOCK(&ifp->if_snd); 136 IFQ_POLL_NOLOCK(&ifp->if_snd, m); 137 if (m != NULL && func(m, arg) == 0) { 138 IFQ_UNLOCK(&ifp->if_snd); 139 return (NULL); 140 } 141 IFQ_DEQUEUE_NOLOCK(&ifp->if_snd, m); 142 IFQ_UNLOCK(&ifp->if_snd); 143 return (m); 144 } 145 m = (struct mbuf *)buf_ring_peek(br); 146 if (m == NULL || func(m, arg) == 0) 147 return (NULL); 148 149 return ((struct mbuf *)buf_ring_dequeue_sc(br)); 150 } 151 152 int 153 drbr_empty(struct ifnet *ifp, struct buf_ring *br) 154 { 155 if (ALTQ_IS_ENABLED(&ifp->if_snd)) 156 return (IFQ_IS_EMPTY(&ifp->if_snd)); 157 return (buf_ring_empty(br)); 158 } 159 160 int 161 drbr_needs_enqueue(struct ifnet *ifp, struct buf_ring *br) 162 { 163 if (ALTQ_IS_ENABLED(&ifp->if_snd)) 164 return (1); 165 return (!buf_ring_empty(br)); 166 } 167 168 int 169 drbr_inuse(struct ifnet *ifp, struct buf_ring *br) 170 { 171 if (ALTQ_IS_ENABLED(&ifp->if_snd)) 172 return (ifp->if_snd.ifq_len); 173 return (buf_ring_count(br)); 174 } 175 176