sys/dev/netmap/if_em_netmap.h

   1 /*
   2  * Copyright (C) 2011 Matteo Landi, Luigi Rizzo. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  */
  25
  26 /*
  27  * $FreeBSD$
  28  *
  29  * netmap support for em.
  30  *
  31  * For more details on netmap support please see ixgbe_netmap.h
  32  */
  33
  34
  35 #include <net/netmap.h>
  36 #include <sys/selinfo.h>
  37 #include <vm/vm.h>
  38 #include <vm/pmap.h>    /* vtophys ? */
  39 #include <dev/netmap/netmap_kern.h>
  40
  41
  42 static void     em_netmap_block_tasks(struct adapter *);
  43 static void     em_netmap_unblock_tasks(struct adapter *);
  44
  45
  46 static void
  47 em_netmap_lock_wrapper(struct ifnet *ifp, int what, u_int queueid)
  48 {
  49         struct adapter *adapter = ifp->if_softc;
  50
  51         ASSERT(queueid < adapter->num_queues);
  52         switch (what) {
  53         case NETMAP_CORE_LOCK:
  54                 EM_CORE_LOCK(adapter);
  55                 break;
  56         case NETMAP_CORE_UNLOCK:
  57                 EM_CORE_UNLOCK(adapter);
  58                 break;
  59         case NETMAP_TX_LOCK:
  60                 EM_TX_LOCK(&adapter->tx_rings[queueid]);
  61                 break;
  62         case NETMAP_TX_UNLOCK:
  63                 EM_TX_UNLOCK(&adapter->tx_rings[queueid]);
  64                 break;
  65         case NETMAP_RX_LOCK:
  66                 EM_RX_LOCK(&adapter->rx_rings[queueid]);
  67                 break;
  68         case NETMAP_RX_UNLOCK:
  69                 EM_RX_UNLOCK(&adapter->rx_rings[queueid]);
  70                 break;
  71         }
  72 }
  73
  74
  75 // XXX do we need to block/unblock the tasks ?
  76 static void
  77 em_netmap_block_tasks(struct adapter *adapter)
  78 {
  79         if (adapter->msix > 1) { /* MSIX */
  80                 int i;
  81                 struct tx_ring *txr = adapter->tx_rings;
  82                 struct rx_ring *rxr = adapter->rx_rings;
  83
  84                 for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
  85                         taskqueue_block(txr->tq);
  86                         taskqueue_drain(txr->tq, &txr->tx_task);
  87                         taskqueue_block(rxr->tq);
  88                         taskqueue_drain(rxr->tq, &rxr->rx_task);
  89                 }
  90         } else {        /* legacy */
  91                 taskqueue_block(adapter->tq);
  92                 taskqueue_drain(adapter->tq, &adapter->link_task);
  93                 taskqueue_drain(adapter->tq, &adapter->que_task);
  94         }
  95 }
  96
  97
  98 static void
  99 em_netmap_unblock_tasks(struct adapter *adapter)
 100 {
 101         if (adapter->msix > 1) {
 102                 struct tx_ring *txr = adapter->tx_rings;
 103                 struct rx_ring *rxr = adapter->rx_rings;
 104                 int i;
 105
 106                 for (i = 0; i < adapter->num_queues; i++) {
 107                         taskqueue_unblock(txr->tq);
 108                         taskqueue_unblock(rxr->tq);
 109                 }
 110         } else { /* legacy */
 111                 taskqueue_unblock(adapter->tq);
 112         }
 113 }
 114
 115
 116 /*
 117  * Register/unregister routine
 118  */
 119 static int
 120 em_netmap_reg(struct ifnet *ifp, int onoff)
 121 {
 122         struct adapter *adapter = ifp->if_softc;
 123         struct netmap_adapter *na = NA(ifp);
 124         int error = 0;
 125
 126         if (na == NULL)
 127                 return EINVAL;  /* no netmap support here */
 128
 129         em_disable_intr(adapter);
 130
 131         /* Tell the stack that the interface is no longer active */
 132         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
 133
 134         em_netmap_block_tasks(adapter);
 135
 136         if (onoff) {
 137                 ifp->if_capenable |= IFCAP_NETMAP;
 138
 139                 na->if_transmit = ifp->if_transmit;
 140                 ifp->if_transmit = netmap_start;
 141
 142                 em_init_locked(adapter);
 143                 if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) == 0) {
 144                         error = ENOMEM;
 145                         goto fail;
 146                 }
 147         } else {
 148 fail:
 149                 /* return to non-netmap mode */
 150                 ifp->if_transmit = na->if_transmit;
 151                 ifp->if_capenable &= ~IFCAP_NETMAP;
 152                 em_init_locked(adapter);        /* also enable intr */
 153         }
 154         em_netmap_unblock_tasks(adapter);
 155         return (error);
 156 }
 157
 158
 159 /*
 160  * Reconcile kernel and user view of the transmit ring.
 161  */
 162 static int
 163 em_netmap_txsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 164 {
 165         struct adapter *adapter = ifp->if_softc;
 166         struct tx_ring *txr = &adapter->tx_rings[ring_nr];
 167         struct netmap_adapter *na = NA(ifp);
 168         struct netmap_kring *kring = &na->tx_rings[ring_nr];
 169         struct netmap_ring *ring = kring->ring;
 170         u_int j, k, l, n = 0, lim = kring->nkr_num_slots - 1;
 171
 172         /* generate an interrupt approximately every half ring */
 173         u_int report_frequency = kring->nkr_num_slots >> 1;
 174
 175         k = ring->cur;
 176         if (k > lim)
 177                 return netmap_ring_reinit(kring);
 178
 179         if (do_lock)
 180                 EM_TX_LOCK(txr);
 181         bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 182                         BUS_DMASYNC_POSTREAD);
 183
 184         /*
 185          * Process new packets to send. j is the current index in the
 186          * netmap ring, l is the corresponding index in the NIC ring.
 187          */
 188         j = kring->nr_hwcur;
 189         if (j != k) {   /* we have new packets to send */
 190                 l = netmap_idx_k2n(kring, j);
 191                 for (n = 0; j != k; n++) {
 192                         /* slot is the current slot in the netmap ring */
 193                         struct netmap_slot *slot = &ring->slot[j];
 194                         /* curr is the current slot in the nic ring */
 195                         struct e1000_tx_desc *curr = &txr->tx_base[l];
 196                         struct em_buffer *txbuf = &txr->tx_buffers[l];
 197                         int flags = ((slot->flags & NS_REPORT) ||
 198                                 j == 0 || j == report_frequency) ?
 199                                         E1000_TXD_CMD_RS : 0;
 200                         uint64_t paddr;
 201                         void *addr = PNMB(slot, &paddr);
 202                         u_int len = slot->len;
 203
 204                         if (addr == netmap_buffer_base || len > NETMAP_BUF_SIZE) {
 205                                 if (do_lock)
 206                                         EM_TX_UNLOCK(txr);
 207                                 return netmap_ring_reinit(kring);
 208                         }
 209
 210                         slot->flags &= ~NS_REPORT;
 211                         if (slot->flags & NS_BUF_CHANGED) {
 212                                 curr->buffer_addr = htole64(paddr);
 213                                 /* buffer has changed, reload map */
 214                                 netmap_reload_map(txr->txtag, txbuf->map, addr);
 215                                 slot->flags &= ~NS_BUF_CHANGED;
 216                         }
 217                         curr->upper.data = 0;
 218                         curr->lower.data = htole32(adapter->txd_cmd | len |
 219                                 (E1000_TXD_CMD_EOP | flags) );
 220                         bus_dmamap_sync(txr->txtag, txbuf->map,
 221                                 BUS_DMASYNC_PREWRITE);
 222                         j = (j == lim) ? 0 : j + 1;
 223                         l = (l == lim) ? 0 : l + 1;
 224                 }
 225                 kring->nr_hwcur = k; /* the saved ring->cur */
 226                 kring->nr_hwavail -= n;
 227
 228                 bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 229                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 230
 231                 E1000_WRITE_REG(&adapter->hw, E1000_TDT(txr->me), l);
 232         }
 233
 234         if (n == 0 || kring->nr_hwavail < 1) {
 235                 int delta;
 236
 237                 /* record completed transmissions using TDH */
 238                 l = E1000_READ_REG(&adapter->hw, E1000_TDH(ring_nr));
 239                 if (l >= kring->nkr_num_slots) { /* XXX can it happen ? */
 240                         D("TDH wrap %d", l);
 241                         l -= kring->nkr_num_slots;
 242                 }
 243                 delta = l - txr->next_to_clean;
 244                 if (delta) {
 245                         /* some completed, increment hwavail. */
 246                         if (delta < 0)
 247                                 delta += kring->nkr_num_slots;
 248                         txr->next_to_clean = l;
 249                         kring->nr_hwavail += delta;
 250                 }
 251         }
 252         /* update avail to what the kernel knows */
 253         ring->avail = kring->nr_hwavail;
 254
 255         if (do_lock)
 256                 EM_TX_UNLOCK(txr);
 257         return 0;
 258 }
 259
 260
 261 /*
 262  * Reconcile kernel and user view of the receive ring.
 263  */
 264 static int
 265 em_netmap_rxsync(struct ifnet *ifp, u_int ring_nr, int do_lock)
 266 {
 267         struct adapter *adapter = ifp->if_softc;
 268         struct rx_ring *rxr = &adapter->rx_rings[ring_nr];
 269         struct netmap_adapter *na = NA(ifp);
 270         struct netmap_kring *kring = &na->rx_rings[ring_nr];
 271         struct netmap_ring *ring = kring->ring;
 272         u_int j, l, n, lim = kring->nkr_num_slots - 1;
 273         int force_update = do_lock || kring->nr_kflags & NKR_PENDINTR;
 274         u_int k = ring->cur, resvd = ring->reserved;
 275
 276         k = ring->cur;
 277         if (k > lim)
 278                 return netmap_ring_reinit(kring);
 279
 280         if (do_lock)
 281                 EM_RX_LOCK(rxr);
 282
 283         /* XXX check sync modes */
 284         bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
 285                         BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
 286
 287         /*
 288          * Import newly received packets into the netmap ring.
 289          * j is an index in the netmap ring, l in the NIC ring.
 290          */
 291         l = rxr->next_to_check;
 292         j = netmap_idx_n2k(kring, l);
 293         if (netmap_no_pendintr || force_update) {
 294                 uint16_t slot_flags = kring->nkr_slot_flags;
 295
 296                 for (n = 0; ; n++) {
 297                         struct e1000_rx_desc *curr = &rxr->rx_base[l];
 298                         uint32_t staterr = le32toh(curr->status);
 299
 300                         if ((staterr & E1000_RXD_STAT_DD) == 0)
 301                                 break;
 302                         ring->slot[j].len = le16toh(curr->length);
 303                         ring->slot[j].flags = slot_flags;
 304                         bus_dmamap_sync(rxr->rxtag, rxr->rx_buffers[l].map,
 305                                 BUS_DMASYNC_POSTREAD);
 306                         j = (j == lim) ? 0 : j + 1;
 307                         /* make sure next_to_refresh follows next_to_check */
 308                         rxr->next_to_refresh = l;       // XXX
 309                         l = (l == lim) ? 0 : l + 1;
 310                 }
 311                 if (n) { /* update the state variables */
 312                         rxr->next_to_check = l;
 313                         kring->nr_hwavail += n;
 314                 }
 315                 kring->nr_kflags &= ~NKR_PENDINTR;
 316         }
 317
 318         /* skip past packets that userspace has released */
 319         j = kring->nr_hwcur;    /* netmap ring index */
 320         if (resvd > 0) {
 321                 if (resvd + ring->avail >= lim + 1) {
 322                         D("XXX invalid reserve/avail %d %d", resvd, ring->avail);
 323                         ring->reserved = resvd = 0; // XXX panic...
 324                 }
 325                 k = (k >= resvd) ? k - resvd : k + lim + 1 - resvd;
 326         }
 327         if (j != k) { /* userspace has released some packets. */
 328                 l = netmap_idx_k2n(kring, j); /* NIC ring index */
 329                 for (n = 0; j != k; n++) {
 330                         struct netmap_slot *slot = &ring->slot[j];
 331                         struct e1000_rx_desc *curr = &rxr->rx_base[l];
 332                         struct em_buffer *rxbuf = &rxr->rx_buffers[l];
 333                         uint64_t paddr;
 334                         void *addr = PNMB(slot, &paddr);
 335
 336                         if (addr == netmap_buffer_base) { /* bad buf */
 337                                 if (do_lock)
 338                                         EM_RX_UNLOCK(rxr);
 339                                 return netmap_ring_reinit(kring);
 340                         }
 341
 342                         if (slot->flags & NS_BUF_CHANGED) {
 343                                 curr->buffer_addr = htole64(paddr);
 344                                 /* buffer has changed, reload map */
 345                                 netmap_reload_map(rxr->rxtag, rxbuf->map, addr);
 346                                 slot->flags &= ~NS_BUF_CHANGED;
 347                         }
 348                         curr->status = 0;
 349                         bus_dmamap_sync(rxr->rxtag, rxbuf->map,
 350                             BUS_DMASYNC_PREREAD);
 351                         j = (j == lim) ? 0 : j + 1;
 352                         l = (l == lim) ? 0 : l + 1;
 353                 }
 354                 kring->nr_hwavail -= n;
 355                 kring->nr_hwcur = k;
 356                 bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
 357                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 358                 /*
 359                  * IMPORTANT: we must leave one free slot in the ring,
 360                  * so move l back by one unit
 361                  */
 362                 l = (l == 0) ? lim : l - 1;
 363                 E1000_WRITE_REG(&adapter->hw, E1000_RDT(rxr->me), l);
 364         }
 365         /* tell userspace that there are new packets */
 366         ring->avail = kring->nr_hwavail - resvd;
 367         if (do_lock)
 368                 EM_RX_UNLOCK(rxr);
 369         return 0;
 370 }
 371
 372
 373 static void
 374 em_netmap_attach(struct adapter *adapter)
 375 {
 376         struct netmap_adapter na;
 377
 378         bzero(&na, sizeof(na));
 379
 380         na.ifp = adapter->ifp;
 381         na.separate_locks = 1;
 382         na.num_tx_desc = adapter->num_tx_desc;
 383         na.num_rx_desc = adapter->num_rx_desc;
 384         na.nm_txsync = em_netmap_txsync;
 385         na.nm_rxsync = em_netmap_rxsync;
 386         na.nm_lock = em_netmap_lock_wrapper;
 387         na.nm_register = em_netmap_reg;
 388         netmap_attach(&na, adapter->num_queues);
 389 }
 390
 391 /* end of file */