nicstar.c

来自「linux 内核源代码」· C语言 代码 · 共 2,241 行 · 第 1/5 页

   ns_scqe scqe;
   u32 flags;		/* TBD flags, not CPU flags */
   
   card = vcc->dev->dev_data;
   TXPRINTK("nicstar%d: ns_send() called.\n", card->index);
   if ((vc = (vc_map *) vcc->dev_data) == NULL)
   {
      printk("nicstar%d: vcc->dev_data == NULL on ns_send().\n", card->index);
      atomic_inc(&vcc->stats->tx_err);
      dev_kfree_skb_any(skb);
      return -EINVAL;
   }
   
   if (!vc->tx)
   {
      printk("nicstar%d: Trying to transmit on a non-tx VC.\n", card->index);
      atomic_inc(&vcc->stats->tx_err);
      dev_kfree_skb_any(skb);
      return -EINVAL;
   }
   
   if (vcc->qos.aal != ATM_AAL5 && vcc->qos.aal != ATM_AAL0)
   {
      printk("nicstar%d: Only AAL0 and AAL5 are supported.\n", card->index);
      atomic_inc(&vcc->stats->tx_err);
      dev_kfree_skb_any(skb);
      return -EINVAL;
   }
   
   if (skb_shinfo(skb)->nr_frags != 0)
   {
      printk("nicstar%d: No scatter-gather yet.\n", card->index);
      atomic_inc(&vcc->stats->tx_err);
      dev_kfree_skb_any(skb);
      return -EINVAL;
   }
   
   ATM_SKB(skb)->vcc = vcc;

   if (vcc->qos.aal == ATM_AAL5)
   {
      buflen = (skb->len + 47 + 8) / 48 * 48;	/* Multiple of 48 */
      flags = NS_TBD_AAL5;
      scqe.word_2 = cpu_to_le32((u32) virt_to_bus(skb->data));
      scqe.word_3 = cpu_to_le32((u32) skb->len);
      scqe.word_4 = ns_tbd_mkword_4(0, (u32) vcc->vpi, (u32) vcc->vci, 0,
                           ATM_SKB(skb)->atm_options & ATM_ATMOPT_CLP ? 1 : 0);
      flags |= NS_TBD_EOPDU;
   }
   else /* (vcc->qos.aal == ATM_AAL0) */
   {
      buflen = ATM_CELL_PAYLOAD;	/* i.e., 48 bytes */
      flags = NS_TBD_AAL0;
      scqe.word_2 = cpu_to_le32((u32) virt_to_bus(skb->data) + NS_AAL0_HEADER);
      scqe.word_3 = cpu_to_le32(0x00000000);
      if (*skb->data & 0x02)	/* Payload type 1 - end of pdu */
         flags |= NS_TBD_EOPDU;
      scqe.word_4 = cpu_to_le32(*((u32 *) skb->data) & ~NS_TBD_VC_MASK);
      /* Force the VPI/VCI to be the same as in VCC struct */
      scqe.word_4 |= cpu_to_le32((((u32) vcc->vpi) << NS_TBD_VPI_SHIFT |
                                 ((u32) vcc->vci) << NS_TBD_VCI_SHIFT) &
                                 NS_TBD_VC_MASK);
   }

   if (vcc->qos.txtp.traffic_class == ATM_CBR)
   {
      scqe.word_1 = ns_tbd_mkword_1_novbr(flags, (u32) buflen);
      scq = ((vc_map *) vcc->dev_data)->scq;
   }
   else
   {
      scqe.word_1 = ns_tbd_mkword_1(flags, (u32) 1, (u32) 1, (u32) buflen);
      scq = card->scq0;
   }

   if (push_scqe(card, vc, scq, &scqe, skb) != 0)
   {
      atomic_inc(&vcc->stats->tx_err);
      dev_kfree_skb_any(skb);
      return -EIO;
   }
   atomic_inc(&vcc->stats->tx);

   return 0;
}



static int push_scqe(ns_dev *card, vc_map *vc, scq_info *scq, ns_scqe *tbd,
                     struct sk_buff *skb)
{
   unsigned long flags;
   ns_scqe tsr;
   u32 scdi, scqi;
   int scq_is_vbr;
   u32 data;
   int index;
   
   ns_grab_scq_lock(card, scq, flags);
   while (scq->tail == scq->next)
   {
      if (in_interrupt()) {
         spin_unlock_irqrestore(&scq->lock, flags);
         printk("nicstar%d: Error pushing TBD.\n", card->index);
         return 1;
      }

      scq->full = 1;
      spin_unlock_irqrestore(&scq->lock, flags);
      interruptible_sleep_on_timeout(&scq->scqfull_waitq, SCQFULL_TIMEOUT);
      ns_grab_scq_lock(card, scq, flags);

      if (scq->full) {
         spin_unlock_irqrestore(&scq->lock, flags);
         printk("nicstar%d: Timeout pushing TBD.\n", card->index);
         return 1;
      }
   }
   *scq->next = *tbd;
   index = (int) (scq->next - scq->base);
   scq->skb[index] = skb;
   XPRINTK("nicstar%d: sending skb at 0x%x (pos %d).\n",
           card->index, (u32) skb, index);
   XPRINTK("nicstar%d: TBD written:\n0x%x\n0x%x\n0x%x\n0x%x\n at 0x%x.\n",
           card->index, le32_to_cpu(tbd->word_1), le32_to_cpu(tbd->word_2),
           le32_to_cpu(tbd->word_3), le32_to_cpu(tbd->word_4),
           (u32) scq->next);
   if (scq->next == scq->last)
      scq->next = scq->base;
   else
      scq->next++;

   vc->tbd_count++;
   if (scq->num_entries == VBR_SCQ_NUM_ENTRIES)
   {
      scq->tbd_count++;
      scq_is_vbr = 1;
   }
   else
      scq_is_vbr = 0;

   if (vc->tbd_count >= MAX_TBD_PER_VC || scq->tbd_count >= MAX_TBD_PER_SCQ)
   {
      int has_run = 0;

      while (scq->tail == scq->next)
      {
         if (in_interrupt()) {
            data = (u32) virt_to_bus(scq->next);
            ns_write_sram(card, scq->scd, &data, 1);
            spin_unlock_irqrestore(&scq->lock, flags);
            printk("nicstar%d: Error pushing TSR.\n", card->index);
            return 0;
         }

         scq->full = 1;
         if (has_run++) break;
         spin_unlock_irqrestore(&scq->lock, flags);
         interruptible_sleep_on_timeout(&scq->scqfull_waitq, SCQFULL_TIMEOUT);
         ns_grab_scq_lock(card, scq, flags);
      }

      if (!scq->full)
      {
         tsr.word_1 = ns_tsr_mkword_1(NS_TSR_INTENABLE);
         if (scq_is_vbr)
            scdi = NS_TSR_SCDISVBR;
         else
            scdi = (vc->cbr_scd - NS_FRSCD) / NS_FRSCD_SIZE;
         scqi = scq->next - scq->base;
         tsr.word_2 = ns_tsr_mkword_2(scdi, scqi);
         tsr.word_3 = 0x00000000;
         tsr.word_4 = 0x00000000;

         *scq->next = tsr;
         index = (int) scqi;
         scq->skb[index] = NULL;
         XPRINTK("nicstar%d: TSR written:\n0x%x\n0x%x\n0x%x\n0x%x\n at 0x%x.\n",
                 card->index, le32_to_cpu(tsr.word_1), le32_to_cpu(tsr.word_2),
                 le32_to_cpu(tsr.word_3), le32_to_cpu(tsr.word_4),
		 (u32) scq->next);
         if (scq->next == scq->last)
            scq->next = scq->base;
         else
            scq->next++;
         vc->tbd_count = 0;
         scq->tbd_count = 0;
      }
      else
         PRINTK("nicstar%d: Timeout pushing TSR.\n", card->index);
   }
   data = (u32) virt_to_bus(scq->next);
   ns_write_sram(card, scq->scd, &data, 1);
   
   spin_unlock_irqrestore(&scq->lock, flags);
   
   return 0;
}



static void process_tsq(ns_dev *card)
{
   u32 scdi;
   scq_info *scq;
   ns_tsi *previous = NULL, *one_ahead, *two_ahead;
   int serviced_entries;   /* flag indicating at least on entry was serviced */
   
   serviced_entries = 0;
   
   if (card->tsq.next == card->tsq.last)
      one_ahead = card->tsq.base;
   else
      one_ahead = card->tsq.next + 1;

   if (one_ahead == card->tsq.last)
      two_ahead = card->tsq.base;
   else
      two_ahead = one_ahead + 1;
   
   while (!ns_tsi_isempty(card->tsq.next) || !ns_tsi_isempty(one_ahead) ||
          !ns_tsi_isempty(two_ahead))
          /* At most two empty, as stated in the 77201 errata */
   {
      serviced_entries = 1;
    
      /* Skip the one or two possible empty entries */
      while (ns_tsi_isempty(card->tsq.next)) {
         if (card->tsq.next == card->tsq.last)
            card->tsq.next = card->tsq.base;
         else
            card->tsq.next++;
      }
    
      if (!ns_tsi_tmrof(card->tsq.next))
      {
         scdi = ns_tsi_getscdindex(card->tsq.next);
	 if (scdi == NS_TSI_SCDISVBR)
	    scq = card->scq0;
	 else
	 {
	    if (card->scd2vc[scdi] == NULL)
	    {
	       printk("nicstar%d: could not find VC from SCD index.\n",
	              card->index);
               ns_tsi_init(card->tsq.next);
               return;
            }
            scq = card->scd2vc[scdi]->scq;
         }
         drain_scq(card, scq, ns_tsi_getscqpos(card->tsq.next));
         scq->full = 0;
         wake_up_interruptible(&(scq->scqfull_waitq));
      }

      ns_tsi_init(card->tsq.next);
      previous = card->tsq.next;
      if (card->tsq.next == card->tsq.last)
         card->tsq.next = card->tsq.base;
      else
         card->tsq.next++;

      if (card->tsq.next == card->tsq.last)
         one_ahead = card->tsq.base;
      else
         one_ahead = card->tsq.next + 1;

      if (one_ahead == card->tsq.last)
         two_ahead = card->tsq.base;
      else
         two_ahead = one_ahead + 1;
   }

   if (serviced_entries) {
      writel((((u32) previous) - ((u32) card->tsq.base)),
             card->membase + TSQH);
   }
}



static void drain_scq(ns_dev *card, scq_info *scq, int pos)
{
   struct atm_vcc *vcc;
   struct sk_buff *skb;
   int i;
   unsigned long flags;
   
   XPRINTK("nicstar%d: drain_scq() called, scq at 0x%x, pos %d.\n",
           card->index, (u32) scq, pos);
   if (pos >= scq->num_entries)
   {
      printk("nicstar%d: Bad index on drain_scq().\n", card->index);
      return;
   }

   ns_grab_scq_lock(card, scq, flags);
   i = (int) (scq->tail - scq->base);
   if (++i == scq->num_entries)
      i = 0;
   while (i != pos)
   {
      skb = scq->skb[i];
      XPRINTK("nicstar%d: freeing skb at 0x%x (index %d).\n",
              card->index, (u32) skb, i);
      if (skb != NULL)
      {
         vcc = ATM_SKB(skb)->vcc;
	 if (vcc && vcc->pop != NULL) {
	    vcc->pop(vcc, skb);
	 } else {
	    dev_kfree_skb_irq(skb);
         }
	 scq->skb[i] = NULL;
      }
      if (++i == scq->num_entries)
         i = 0;
   }
   scq->tail = scq->base + pos;
   spin_unlock_irqrestore(&scq->lock, flags);
}



static void process_rsq(ns_dev *card)
{
   ns_rsqe *previous;

   if (!ns_rsqe_valid(card->rsq.next))
      return;
   do {
      dequeue_rx(card, card->rsq.next);
      ns_rsqe_init(card->rsq.next);
      previous = card->rsq.next;
      if (card->rsq.next == card->rsq.last)
         card->rsq.next = card->rsq.base;
      else
         card->rsq.next++;
   } while (ns_rsqe_valid(card->rsq.next));
   writel((((u32) previous) - ((u32) card->rsq.base)),
          card->membase + RSQH);
}



static void dequeue_rx(ns_dev *card, ns_rsqe *rsqe)
{
   u32 vpi, vci;
   vc_map *vc;
   struct sk_buff *iovb;
   struct iovec *iov;
   struct atm_vcc *vcc;
   struct sk_buff *skb;
   unsigned short aal5_len;
   int len;
   u32 stat;

   stat = readl(card->membase + STAT);
   card->sbfqc = ns_stat_sfbqc_get(stat);   
   card->lbfqc = ns_stat_lfbqc_get(stat);

   skb = (struct sk_buff *) le32_to_cpu(rsqe->buffer_handle);
   vpi = ns_rsqe_vpi(rsqe);
   vci = ns_rsqe_vci(rsqe);
   if (vpi >= 1UL << card->vpibits || vci >= 1UL << card->vcibits)
   {
      printk("nicstar%d: SDU received for out-of-range vc %d.%d.\n",
             card->index, vpi, vci);
      recycle_rx_buf(card, skb);
      return;
   }
   
   vc = &(card->vcmap[vpi << card->vcibits | vci]);
   if (!vc->rx)
   {
      RXPRINTK("nicstar%d: SDU received on non-rx vc %d.%d.\n",
             card->index, vpi, vci);
      recycle_rx_buf(card, skb);
      return;
   }

   vcc = vc->rx_vcc;

   if (vcc->qos.aal == ATM_AAL0)
   {
      struct sk_buff *sb;
      unsigned char *cell;
      int i;

      cell = skb->data;
      for (i = ns_rsqe_cellcount(rsqe); i; i--)
      {
         if ((sb = dev_alloc_skb(NS_SMSKBSIZE)) == NULL)
         {
            printk("nicstar%d: Can't allocate buffers for aal0.\n",
                   card->index);
            atomic_add(i,&vcc->stats->rx_drop);
            break;
         }
         if (!atm_charge(vcc, sb->truesize))
         {
            RXPRINTK("nicstar%d: atm_charge() dropped aal0 packets.\n",
                     card->index);
            atomic_add(i-1,&vcc->stats->rx_drop); /* already increased by 1 */
            dev_kfree_skb_any(sb);
            break;
         }
         /* Rebuild the header */
         *((u32 *) sb->data) = le32_to_cpu(rsqe->word_1) << 4 |
                               (ns_rsqe_clp(rsqe) ? 0x00000001 : 0x00000000);
         if (i == 1 && ns_rsqe_eopdu(rsqe))
            *((u32 *) sb->data) |= 0x00000002;
         skb_put(sb, NS_AAL0_HEADER);
         memcpy(skb_tail_pointer(sb), cell, ATM_CELL_PAYLOAD);
         skb_put(sb, ATM_CELL_PAYLOAD);
         ATM_SKB(sb)->vcc = vcc;
	 __net_timestamp(sb);
         vcc->push(vcc, sb);
         atomic_inc(&vcc->stats->rx);
         cell += ATM_CELL_PAYLOAD;
      }

      recycle_rx_buf(card, skb);
      return;
   }

   /* To reach this point, the AAL layer can only be AAL5 */

   if ((iovb = vc->rx_iov) == NULL)
   {
      iovb = skb_dequeue(&(card->iovpool.queue));
      if (iovb == NULL)		/* No buffers in the queue */
      {
         iovb = alloc_skb(NS_IOVBUFSIZE, GFP_ATOMIC);
	 if (iovb == NULL)
	 {
	    printk("nicstar%d: Out of iovec buffers.\n", card->index);
            atomic_inc(&vcc->stats->rx_drop);
            recycle_rx_buf(card, skb);
            return;
	 }
         NS_SKB_CB(iovb)->buf_type = BUF_NONE;
      }
      else