sys/dev/netmap/if_em_netmap.h

   1 /*
   2  * Copyright (C) 2011-2014 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 // XXX do we need to block/unblock the tasks ?
  43 static void
  44 em_netmap_block_tasks(struct adapter *adapter)
  45 {
  46         if (adapter->msix > 1) { /* MSIX */
  47                 int i;
  48                 struct tx_ring *txr = adapter->tx_rings;
  49                 struct rx_ring *rxr = adapter->rx_rings;
  50
  51                 for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
  52                         taskqueue_block(txr->tq);
  53                         taskqueue_drain(txr->tq, &txr->tx_task);
  54                         taskqueue_block(rxr->tq);
  55                         taskqueue_drain(rxr->tq, &rxr->rx_task);
  56                 }
  57         } else {        /* legacy */
  58                 taskqueue_block(adapter->tq);
  59                 taskqueue_drain(adapter->tq, &adapter->link_task);
  60                 taskqueue_drain(adapter->tq, &adapter->que_task);
  61         }
  62 }
  63
  64
  65 static void
  66 em_netmap_unblock_tasks(struct adapter *adapter)
  67 {
  68         if (adapter->msix > 1) {
  69                 struct tx_ring *txr = adapter->tx_rings;
  70                 struct rx_ring *rxr = adapter->rx_rings;
  71                 int i;
  72
  73                 for (i = 0; i < adapter->num_queues; i++, txr++, rxr++) {
  74                         taskqueue_unblock(txr->tq);
  75                         taskqueue_unblock(rxr->tq);
  76                 }
  77         } else { /* legacy */
  78                 taskqueue_unblock(adapter->tq);
  79         }
  80 }
  81
  82
  83 /*
  84  * Register/unregister. We are already under netmap lock.
  85  */
  86 static int
  87 em_netmap_reg(struct netmap_adapter *na, int onoff)
  88 {
  89         struct ifnet *ifp = na->ifp;
  90         struct adapter *adapter = ifp->if_softc;
  91
  92         EM_CORE_LOCK(adapter);
  93         em_disable_intr(adapter);
  94
  95         /* Tell the stack that the interface is no longer active */
  96         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  97
  98         em_netmap_block_tasks(adapter);
  99         /* enable or disable flags and callbacks in na and ifp */
 100         if (onoff) {
 101                 nm_set_native_flags(na);
 102         } else {
 103                 nm_clear_native_flags(na);
 104         }
 105         em_init_locked(adapter);        /* also enable intr */
 106         em_netmap_unblock_tasks(adapter);
 107         EM_CORE_UNLOCK(adapter);
 108         return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
 109 }
 110
 111
 112 /*
 113  * Reconcile kernel and user view of the transmit ring.
 114  */
 115 static int
 116 em_netmap_txsync(struct netmap_kring *kring, int flags)
 117 {
 118         struct netmap_adapter *na = kring->na;
 119         struct ifnet *ifp = na->ifp;
 120         struct netmap_ring *ring = kring->ring;
 121         u_int nm_i;     /* index into the netmap ring */
 122         u_int nic_i;    /* index into the NIC ring */
 123         u_int n;
 124         u_int const lim = kring->nkr_num_slots - 1;
 125         u_int const head = kring->rhead;
 126         /* generate an interrupt approximately every half ring */
 127         u_int report_frequency = kring->nkr_num_slots >> 1;
 128
 129         /* device-specific */
 130         struct adapter *adapter = ifp->if_softc;
 131         struct tx_ring *txr = &adapter->tx_rings[kring->ring_id];
 132
 133         bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 134                         BUS_DMASYNC_POSTREAD);
 135
 136         /*
 137          * First part: process new packets to send.
 138          */
 139
 140         nm_i = kring->nr_hwcur;
 141         if (nm_i != head) {     /* we have new packets to send */
 142                 nic_i = netmap_idx_k2n(kring, nm_i);
 143                 for (n = 0; nm_i != head; n++) {
 144                         struct netmap_slot *slot = &ring->slot[nm_i];
 145                         u_int len = slot->len;
 146                         uint64_t paddr;
 147                         void *addr = PNMB(na, slot, &paddr);
 148
 149                         /* device-specific */
 150                         struct e1000_tx_desc *curr = &txr->tx_base[nic_i];
 151                         struct em_buffer *txbuf = &txr->tx_buffers[nic_i];
 152                         int flags = (slot->flags & NS_REPORT ||
 153                                 nic_i == 0 || nic_i == report_frequency) ?
 154                                 E1000_TXD_CMD_RS : 0;
 155
 156                         NM_CHECK_ADDR_LEN(na, addr, len);
 157
 158                         if (slot->flags & NS_BUF_CHANGED) {
 159                                 curr->buffer_addr = htole64(paddr);
 160                                 /* buffer has changed, reload map */
 161                                 netmap_reload_map(na, txr->txtag, txbuf->map, addr);
 162                         }
 163                         slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
 164
 165                         /* Fill the slot in the NIC ring. */
 166                         curr->upper.data = 0;
 167                         curr->lower.data = htole32(adapter->txd_cmd | len |
 168                                 (E1000_TXD_CMD_EOP | flags) );
 169                         bus_dmamap_sync(txr->txtag, txbuf->map,
 170                                 BUS_DMASYNC_PREWRITE);
 171
 172                         nm_i = nm_next(nm_i, lim);
 173                         nic_i = nm_next(nic_i, lim);
 174                 }
 175                 kring->nr_hwcur = head;
 176
 177                 /* synchronize the NIC ring */
 178                 bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
 179                         BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 180
 181                 /* (re)start the tx unit up to slot nic_i (excluded) */
 182                 E1000_WRITE_REG(&adapter->hw, E1000_TDT(txr->me), nic_i);
 183         }
 184
 185         /*
 186          * Second part: reclaim buffers for completed transmissions.
 187          */
 188         if (flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
 189                 /* record completed transmissions using TDH */
 190                 nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(kring->ring_id));
 191                 if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
 192                         D("TDH wrap %d", nic_i);
 193                         nic_i -= kring->nkr_num_slots;
 194                 }
 195                 if (nic_i != txr->next_to_clean) {
 196                         txr->next_to_clean = nic_i;
 197                         kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
 198                 }
 199         }
 200
 201         nm_txsync_finalize(kring);
 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 = nm_rxsync_prologue(kring);
 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                 uint16_t slot_flags = kring->nkr_slot_flags;
 239
 240                 nic_i = rxr->next_to_check;
 241                 nm_i = netmap_idx_n2k(kring, nic_i);
 242
 243                 for (n = 0; ; n++) { // XXX no need to count
 244                         struct e1000_rx_desc *curr = &rxr->rx_base[nic_i];
 245                         uint32_t staterr = le32toh(curr->status);
 246
 247                         if ((staterr & E1000_RXD_STAT_DD) == 0)
 248                                 break;
 249                         ring->slot[nm_i].len = le16toh(curr->length);
 250                         ring->slot[nm_i].flags = slot_flags;
 251                         bus_dmamap_sync(rxr->rxtag, rxr->rx_buffers[nic_i].map,
 252                                 BUS_DMASYNC_POSTREAD);
 253                         nm_i = nm_next(nm_i, lim);
 254                         /* make sure next_to_refresh follows next_to_check */
 255                         rxr->next_to_refresh = nic_i;   // XXX
 256                         nic_i = nm_next(nic_i, lim);
 257                 }
 258                 if (n) { /* update the state variables */
 259                         rxr->next_to_check = nic_i;
 260                         kring->nr_hwtail = nm_i;
 261                 }
 262                 kring->nr_kflags &= ~NKR_PENDINTR;
 263         }
 264
 265         /*
 266          * Second part: skip past packets that userspace has released.
 267          */
 268         nm_i = kring->nr_hwcur;
 269         if (nm_i != head) {
 270                 nic_i = netmap_idx_k2n(kring, nm_i);
 271                 for (n = 0; nm_i != head; n++) {
 272                         struct netmap_slot *slot = &ring->slot[nm_i];
 273                         uint64_t paddr;
 274                         void *addr = PNMB(na, slot, &paddr);
 275
 276                         struct e1000_rx_desc *curr = &rxr->rx_base[nic_i];
 277                         struct em_buffer *rxbuf = &rxr->rx_buffers[nic_i];
 278
 279                         if (addr == NETMAP_BUF_BASE(na)) /* bad buf */
 280                                 goto ring_reset;
 281
 282                         if (slot->flags & NS_BUF_CHANGED) {
 283                                 /* buffer has changed, reload map */
 284                                 curr->buffer_addr = htole64(paddr);
 285                                 netmap_reload_map(na, rxr->rxtag, rxbuf->map, addr);
 286                                 slot->flags &= ~NS_BUF_CHANGED;
 287                         }
 288                         curr->status = 0;
 289                         bus_dmamap_sync(rxr->rxtag, rxbuf->map,
 290                             BUS_DMASYNC_PREREAD);
 291                         nm_i = nm_next(nm_i, lim);
 292                         nic_i = nm_next(nic_i, lim);
 293                 }
 294                 kring->nr_hwcur = head;
 295
 296                 bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
 297                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 298                 /*
 299                  * IMPORTANT: we must leave one free slot in the ring,
 300                  * so move nic_i back by one unit
 301                  */
 302                 nic_i = nm_prev(nic_i, lim);
 303                 E1000_WRITE_REG(&adapter->hw, E1000_RDT(rxr->me), nic_i);
 304         }
 305
 306         /* tell userspace that there might be new packets */
 307         nm_rxsync_finalize(kring);
 308
 309         return 0;
 310
 311 ring_reset:
 312         return netmap_ring_reinit(kring);
 313 }
 314
 315
 316 static void
 317 em_netmap_attach(struct adapter *adapter)
 318 {
 319         struct netmap_adapter na;
 320
 321         bzero(&na, sizeof(na));
 322
 323         na.ifp = adapter->ifp;
 324         na.na_flags = NAF_BDG_MAYSLEEP;
 325         na.num_tx_desc = adapter->num_tx_desc;
 326         na.num_rx_desc = adapter->num_rx_desc;
 327         na.nm_txsync = em_netmap_txsync;
 328         na.nm_rxsync = em_netmap_rxsync;
 329         na.nm_register = em_netmap_reg;
 330         na.num_tx_rings = na.num_rx_rings = adapter->num_queues;
 331         netmap_attach(&na);
 332 }
 333
 334 /* end of file */