sys/dev/netmap/if_em_netmap.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 /*
  29  * $FreeBSD$
  30  *
  31  * netmap support for: em.
  32  *
  33  * For more details on netmap support please see ixgbe_netmap.h
  34  */
  35
  36
  37 #include <net/netmap.h>
  38 #include <sys/selinfo.h>
  39 #include <vm/vm.h>
  40 #include <vm/pmap.h>    /* vtophys ? */
  41 #include <dev/netmap/netmap_kern.h>
  42
  43
  44 // XXX do we need to block/unblock the tasks ?
  45 static void
  46 em_netmap_block_tasks(struct adapter *adapter)
  47 {
  48         if (adapter->msix > 1) { /* MSIX */
  49                 int i;
  50                 struct tx_ring *txr = adapter->tx_rings;
  51                 struct rx_ring *rxr = adapter->rx_rings;
  52
  53                 for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
  54                         taskqueue_block(txr->tq);
  55                         taskqueue_drain(txr->tq, &txr->tx_task);
  56                         taskqueue_block(rxr->tq);
  57                         taskqueue_drain(rxr->tq, &rxr->rx_task);
  58                 }
  59         } else {        /* legacy */
  60                 taskqueue_block(adapter->tq);
  61                 taskqueue_drain(adapter->tq, &adapter->link_task);
  62                 taskqueue_drain(adapter->tq, &adapter->que_task);
  63         }
  64 }
  65
  66
  67 static void
  68 em_netmap_unblock_tasks(struct adapter *adapter)
  69 {
  70         if (adapter->msix > 1) {
  71                 struct tx_ring *txr = adapter->tx_rings;
  72                 struct rx_ring *rxr = adapter->rx_rings;
  73                 int i;
  74
  75                 for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
  76                         taskqueue_unblock(txr->tq);
  77                         taskqueue_unblock(rxr->tq);
  78                 }
  79         } else { /* legacy */
  80                 taskqueue_unblock(adapter->tq);
  81         }
  82 }
  83
  84
  85 /*
  86  * Register/unregister. We are already under netmap lock.
  87  */
  88 static int
  89 em_netmap_reg(struct netmap_adapter *na, int onoff)
  90 {
  91         struct ifnet *ifp = na->ifp;
  92         struct adapter *adapter = ifp->if_softc;
  93
  94         EM_CORE_LOCK(adapter);
  95         em_disable_intr(adapter);
  96
  97         /* Tell the stack that the interface is no longer active */
  98         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  99
 100         em_netmap_block_tasks(adapter);
 101         /* enable or disable flags and callbacks in na and ifp */
 102         if (onoff) {
 103                 nm_set_native_flags(na);
 104         } else {
 105                 nm_clear_native_flags(na);
 106         }
 107         em_init_locked(adapter);        /* also enable intr */
 108         em_netmap_unblock_tasks(adapter);
 109         EM_CORE_UNLOCK(adapter);
 110         return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
 111 }
 112
 113
 114 /*
 115  * Reconcile kernel and user view of the transmit ring.
 116  */
 117 static int
 118 em_netmap_txsync(struct netmap_kring *kring, int flags)
 119 {
 120         struct netmap_adapter *na = kring->na;
 121         struct ifnet *ifp = na->ifp;
 122         struct netmap_ring *ring = kring->ring;
 123         u_int nm_i;     /* index into the netmap ring */
 124         u_int nic_i;    /* index into the NIC ring */
 125         u_int n;
 126         u_int const lim = kring->nkr_num_slots - 1;
 127         u_int const head = kring->rhead;
 128         /* generate an interrupt approximately every half ring */
 129         u_int report_frequency = kring->nkr_num_slots >> 1;
 130
 131         /* device-specific */
 132         struct adapter *adapter = ifp->if_softc;
 133         struct tx_ring *txr = &adapter->tx_rings[kring->ring_id];
 134
 135         bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 136                         BUS_DMASYNC_POSTREAD);
 137
 138         /*
 139          * First part: process new packets to send.
 140          */
 141
 142         nm_i = kring->nr_hwcur;
 143         if (nm_i != head) {     /* we have new packets to send */
 144                 nic_i = netmap_idx_k2n(kring, nm_i);
 145                 for (n = 0; nm_i != head; n++) {
 146                         struct netmap_slot *slot = &ring->slot[nm_i];
 147                         u_int len = slot->len;
 148                         uint64_t paddr;
 149                         void *addr = PNMB(na, slot, &paddr);
 150
 151                         /* device-specific */
 152                         struct e1000_tx_desc *curr = &txr->tx_base[nic_i];
 153                         struct em_txbuffer *txbuf = &txr->tx_buffers[nic_i];
 154                         int flags = (slot->flags & NS_REPORT ||
 155                                 nic_i == 0 || nic_i == report_frequency) ?
 156                                 E1000_TXD_CMD_RS : 0;
 157
 158                         NM_CHECK_ADDR_LEN(na, addr, len);
 159
 160                         if (slot->flags & NS_BUF_CHANGED) {
 161                                 curr->buffer_addr = htole64(paddr);
 162                                 /* buffer has changed, reload map */
 163                                 netmap_reload_map(na, txr->txtag, txbuf->map, addr);
 164                         }
 165                         slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
 166
 167                         /* Fill the slot in the NIC ring. */
 168                         curr->upper.data = 0;
 169                         curr->lower.data = htole32(adapter->txd_cmd | len |
 170                                 (E1000_TXD_CMD_EOP | flags) );
 171                         bus_dmamap_sync(txr->txtag, txbuf->map,
 172                                 BUS_DMASYNC_PREWRITE);
 173
 174                         nm_i = nm_next(nm_i, lim);
 175                         nic_i = nm_next(nic_i, lim);
 176                 }
 177                 kring->nr_hwcur = head;
 178
 179                 /* synchronize the NIC ring */
 180                 bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 181                         BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 182
 183                 /* (re)start the tx unit up to slot nic_i (excluded) */
 184                 E1000_WRITE_REG(&adapter->hw, E1000_TDT(txr->me), nic_i);
 185         }
 186
 187         /*
 188          * Second part: reclaim buffers for completed transmissions.
 189          */
 190         if (flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
 191                 /* record completed transmissions using TDH */
 192                 nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(kring->ring_id));
 193                 if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
 194                         D("TDH wrap %d", nic_i);
 195                         nic_i -= kring->nkr_num_slots;
 196                 }
 197                 if (nic_i != txr->next_to_clean) {
 198                         txr->next_to_clean = nic_i;
 199                         kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
 200                 }
 201         }
 202
 203         return 0;
 204 }
 205
 206
 207 /*
 208  * Reconcile kernel and user view of the receive ring.
 209  */
 210 static int
 211 em_netmap_rxsync(struct netmap_kring *kring, int flags)
 212 {
 213         struct netmap_adapter *na = kring->na;
 214         struct ifnet *ifp = na->ifp;
 215         struct netmap_ring *ring = kring->ring;
 216         u_int nm_i;     /* index into the netmap ring */
 217         u_int nic_i;    /* index into the NIC ring */
 218         u_int n;
 219         u_int const lim = kring->nkr_num_slots - 1;
 220         u_int const head = kring->rhead;
 221         int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
 222
 223         /* device-specific */
 224         struct adapter *adapter = ifp->if_softc;
 225         struct rx_ring *rxr = &adapter->rx_rings[kring->ring_id];
 226
 227         if (head > lim)
 228                 return netmap_ring_reinit(kring);
 229
 230         /* XXX check sync modes */
 231         bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
 232                         BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
 233
 234         /*
 235          * First part: import newly received packets.
 236          */
 237         if (netmap_no_pendintr || force_update) {
 238                 nic_i = rxr->next_to_check;
 239                 nm_i = netmap_idx_n2k(kring, nic_i);
 240
 241                 for (n = 0; ; n++) { // XXX no need to count
 242                         union e1000_rx_desc_extended *curr = &rxr->rx_base[nic_i];
 243                         uint32_t staterr = le32toh(curr->wb.upper.status_error);
 244
 245                         if ((staterr & E1000_RXD_STAT_DD) == 0)
 246                                 break;
 247                         ring->slot[nm_i].len = le16toh(curr->wb.upper.length);
 248                         ring->slot[nm_i].flags = 0;
 249                         bus_dmamap_sync(rxr->rxtag, rxr->rx_buffers[nic_i].map,
 250                                 BUS_DMASYNC_POSTREAD);
 251                         nm_i = nm_next(nm_i, lim);
 252                         /* make sure next_to_refresh follows next_to_check */
 253                         rxr->next_to_refresh = nic_i;   // XXX
 254                         nic_i = nm_next(nic_i, lim);
 255                 }
 256                 if (n) { /* update the state variables */
 257                         rxr->next_to_check = nic_i;
 258                         kring->nr_hwtail = nm_i;
 259                 }
 260                 kring->nr_kflags &= ~NKR_PENDINTR;
 261         }
 262
 263         /*
 264          * Second part: skip past packets that userspace has released.
 265          */
 266         nm_i = kring->nr_hwcur;
 267         if (nm_i != head) {
 268                 nic_i = netmap_idx_k2n(kring, nm_i);
 269                 for (n = 0; nm_i != head; n++) {
 270                         struct netmap_slot *slot = &ring->slot[nm_i];
 271                         uint64_t paddr;
 272                         void *addr = PNMB(na, slot, &paddr);
 273
 274                         union e1000_rx_desc_extended *curr = &rxr->rx_base[nic_i];
 275                         struct em_rxbuffer *rxbuf = &rxr->rx_buffers[nic_i];
 276
 277                         if (addr == NETMAP_BUF_BASE(na)) /* bad buf */
 278                                 goto ring_reset;
 279
 280                         curr->read.buffer_addr = htole64(paddr);
 281                         if (slot->flags & NS_BUF_CHANGED) {
 282                                 /* buffer has changed, reload map */
 283                                 netmap_reload_map(na, rxr->rxtag, rxbuf->map, addr);
 284                                 slot->flags &= ~NS_BUF_CHANGED;
 285                         }
 286                         curr->wb.upper.status_error = 0;
 287                         bus_dmamap_sync(rxr->rxtag, rxbuf->map,
 288                             BUS_DMASYNC_PREREAD);
 289                         nm_i = nm_next(nm_i, lim);
 290                         nic_i = nm_next(nic_i, lim);
 291                 }
 292                 kring->nr_hwcur = head;
 293
 294                 bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
 295                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 296                 /*
 297                  * IMPORTANT: we must leave one free slot in the ring,
 298                  * so move nic_i back by one unit
 299                  */
 300                 nic_i = nm_prev(nic_i, lim);
 301                 E1000_WRITE_REG(&adapter->hw, E1000_RDT(rxr->me), nic_i);
 302         }
 303
 304         return 0;
 305
 306 ring_reset:
 307         return netmap_ring_reinit(kring);
 308 }
 309
 310
 311 static void
 312 em_netmap_attach(struct adapter *adapter)
 313 {
 314         struct netmap_adapter na;
 315
 316         bzero(&na, sizeof(na));
 317
 318         na.ifp = adapter->ifp;
 319         na.na_flags = NAF_BDG_MAYSLEEP;
 320         na.num_tx_desc = adapter->num_tx_desc;
 321         na.num_rx_desc = adapter->num_rx_desc;
 322         na.nm_txsync = em_netmap_txsync;
 323         na.nm_rxsync = em_netmap_rxsync;
 324         na.nm_register = em_netmap_reg;
 325         na.num_tx_rings = na.num_rx_rings = adapter->num_queues;
 326         netmap_attach(&na);
 327 }
 328
 329 /* end of file */