C++ skb_copy_to_linear_data函数代码示例

/**
 * tipc_msg_build - create buffer chain containing specified header and data
 * @mhdr: Message header, to be prepended to data
 * @m: User message
 * @offset: Posision in iov to start copying from
 * @dsz: Total length of user data
 * @pktmax: Max packet size that can be used
 * @list: Buffer or chain of buffers to be returned to caller
 *
 * Returns message data size or errno: -ENOMEM, -EFAULT
 */
int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, int offset,
		   int dsz, int pktmax, struct sk_buff_head *list)
{
	int mhsz = msg_hdr_sz(mhdr);
	int msz = mhsz + dsz;
	int pktno = 1;
	int pktsz;
	int pktrem = pktmax;
	int drem = dsz;
	struct tipc_msg pkthdr;
	struct sk_buff *skb;
	char *pktpos;
	int rc;

	msg_set_size(mhdr, msz);

	/* No fragmentation needed? */
	if (likely(msz <= pktmax)) {
		skb = tipc_buf_acquire(msz);
		if (unlikely(!skb))
			return -ENOMEM;
		__skb_queue_tail(list, skb);
		skb_copy_to_linear_data(skb, mhdr, mhsz);
		pktpos = skb->data + mhsz;
		if (!dsz || !memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset,
						 dsz))
			return dsz;
		rc = -EFAULT;
		goto error;
	}

	/* Prepare reusable fragment header */
	tipc_msg_init(&pkthdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
		      INT_H_SIZE, msg_destnode(mhdr));
	msg_set_size(&pkthdr, pktmax);
	msg_set_fragm_no(&pkthdr, pktno);

	/* Prepare first fragment */
	skb = tipc_buf_acquire(pktmax);
	if (!skb)
		return -ENOMEM;
	__skb_queue_tail(list, skb);
	pktpos = skb->data;
	skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
	pktpos += INT_H_SIZE;
	pktrem -= INT_H_SIZE;
	skb_copy_to_linear_data_offset(skb, INT_H_SIZE, mhdr, mhsz);
	pktpos += mhsz;
	pktrem -= mhsz;

	do {
		if (drem < pktrem)
			pktrem = drem;

		if (memcpy_fromiovecend(pktpos, m->msg_iter.iov, offset, pktrem)) {
			rc = -EFAULT;
			goto error;
		}
		drem -= pktrem;
		offset += pktrem;

		if (!drem)
			break;

		/* Prepare new fragment: */
		if (drem < (pktmax - INT_H_SIZE))
			pktsz = drem + INT_H_SIZE;
		else
			pktsz = pktmax;
		skb = tipc_buf_acquire(pktsz);
		if (!skb) {
			rc = -ENOMEM;
			goto error;
		}
		__skb_queue_tail(list, skb);
		msg_set_type(&pkthdr, FRAGMENT);
		msg_set_size(&pkthdr, pktsz);
		msg_set_fragm_no(&pkthdr, ++pktno);
		skb_copy_to_linear_data(skb, &pkthdr, INT_H_SIZE);
		pktpos = skb->data + INT_H_SIZE;
		pktrem = pktsz - INT_H_SIZE;

	} while (1);
	msg_set_type(buf_msg(skb), LAST_FRAGMENT);
	return dsz;
error:
	__skb_queue_purge(list);
	__skb_queue_head_init(list);
	return rc;
//.........这里部分代码省略.........

static int ip6mr_cache_report(struct sk_buff *pkt, mifi_t mifi, int assert)
{
	struct sk_buff *skb;
	struct mrt6msg *msg;
	int ret;

#ifdef CONFIG_IPV6_PIMSM_V2
	if (assert == MRT6MSG_WHOLEPKT)
		skb = skb_realloc_headroom(pkt, -skb_network_offset(pkt)
						+sizeof(*msg));
	else
#endif
		skb = alloc_skb(sizeof(struct ipv6hdr) + sizeof(*msg), GFP_ATOMIC);

	if (!skb)
		return -ENOBUFS;

	/* I suppose that internal messages
	 * do not require checksums */

	skb->ip_summed = CHECKSUM_UNNECESSARY;

#ifdef CONFIG_IPV6_PIMSM_V2
	if (assert == MRT6MSG_WHOLEPKT) {
		/* Ugly, but we have no choice with this interface.
		   Duplicate old header, fix length etc.
		   And all this only to mangle msg->im6_msgtype and
		   to set msg->im6_mbz to "mbz" :-)
		 */
		skb_push(skb, -skb_network_offset(pkt));

		skb_push(skb, sizeof(*msg));
		skb_reset_transport_header(skb);
		msg = (struct mrt6msg *)skb_transport_header(skb);
		msg->im6_mbz = 0;
		msg->im6_msgtype = MRT6MSG_WHOLEPKT;
		msg->im6_mif = reg_vif_num;
		msg->im6_pad = 0;
		ipv6_addr_copy(&msg->im6_src, &ipv6_hdr(pkt)->saddr);
		ipv6_addr_copy(&msg->im6_dst, &ipv6_hdr(pkt)->daddr);

		skb->ip_summed = CHECKSUM_UNNECESSARY;
	} else
#endif
	{
	/*
	 *	Copy the IP header
	 */

	skb_put(skb, sizeof(struct ipv6hdr));
	skb_reset_network_header(skb);
	skb_copy_to_linear_data(skb, ipv6_hdr(pkt), sizeof(struct ipv6hdr));

	/*
	 *	Add our header
	 */
	skb_put(skb, sizeof(*msg));
	skb_reset_transport_header(skb);
	msg = (struct mrt6msg *)skb_transport_header(skb);

	msg->im6_mbz = 0;
	msg->im6_msgtype = assert;
	msg->im6_mif = mifi;
	msg->im6_pad = 0;
	ipv6_addr_copy(&msg->im6_src, &ipv6_hdr(pkt)->saddr);
	ipv6_addr_copy(&msg->im6_dst, &ipv6_hdr(pkt)->daddr);

	skb->dst = dst_clone(pkt->dst);
	skb->ip_summed = CHECKSUM_UNNECESSARY;

	skb_pull(skb, sizeof(struct ipv6hdr));
	}

	if (mroute6_socket == NULL) {
		kfree_skb(skb);
		return -EINVAL;
	}

	/*
	 *	Deliver to user space multicast routing algorithms
	 */
	if ((ret = sock_queue_rcv_skb(mroute6_socket, skb)) < 0) {
		if (net_ratelimit())
			printk(KERN_WARNING "mroute6: pending queue full, dropping entries.\n");
		kfree_skb(skb);
	}

	return ret;
}

static void sun3_82586_rcv_int(struct net_device *dev)
{
	int status,cnt=0;
	unsigned short totlen;
	struct sk_buff *skb;
	struct rbd_struct *rbd;
	struct priv *p = netdev_priv(dev);

	if(debuglevel > 0)
		printk("R");

	for(;(status = p->rfd_top->stat_high) & RFD_COMPL;)
	{
			rbd = (struct rbd_struct *) make32(p->rfd_top->rbd_offset);

			if(status & RFD_OK) /* frame received without error? */
			{
				if( (totlen = swab16(rbd->status)) & RBD_LAST) /* the first and the last buffer? */
				{
					totlen &= RBD_MASK; /* length of this frame */
					rbd->status = 0;
					skb = (struct sk_buff *) dev_alloc_skb(totlen+2);
					if(skb != NULL)
					{
						skb_reserve(skb,2);
						skb_put(skb,totlen);
						skb_copy_to_linear_data(skb,(char *) p->base+swab32((unsigned long) rbd->buffer),totlen);
						skb->protocol=eth_type_trans(skb,dev);
						netif_rx(skb);
						p->stats.rx_packets++;
					}
					else
						p->stats.rx_dropped++;
				}
				else
				{
					int rstat;
						 /* free all RBD's until RBD_LAST is set */
					totlen = 0;
					while(!((rstat=swab16(rbd->status)) & RBD_LAST))
					{
						totlen += rstat & RBD_MASK;
						if(!rstat)
						{
							printk("%s: Whoops .. no end mark in RBD list\n",dev->name);
							break;
						}
						rbd->status = 0;
						rbd = (struct rbd_struct *) make32(rbd->next);
					}
					totlen += rstat & RBD_MASK;
					rbd->status = 0;
					printk("%s: received oversized frame! length: %d\n",dev->name,totlen);
					p->stats.rx_dropped++;
			 }
		}
		else /* frame !(ok), only with 'save-bad-frames' */
		{
			printk("%s: oops! rfd-error-status: %04x\n",dev->name,status);
			p->stats.rx_errors++;
		}
		p->rfd_top->stat_high = 0;
		p->rfd_top->last = RFD_SUSP; /* maybe exchange by RFD_LAST */
		p->rfd_top->rbd_offset = 0xffff;
		p->rfd_last->last = 0;				/* delete RFD_SUSP	*/
		p->rfd_last = p->rfd_top;
		p->rfd_top = (struct rfd_struct *) make32(p->rfd_top->next); /* step to next RFD */
		p->scb->rfa_offset = make16(p->rfd_top);

		if(debuglevel > 0)
			printk("%d",cnt++);
	}

	if(automatic_resume)
	{
		WAIT_4_SCB_CMD();
		p->scb->cmd_ruc = RUC_RESUME;
		sun3_attn586();
		WAIT_4_SCB_CMD_RUC();
	}

#ifdef WAIT_4_BUSY
	{
		int i;
		for(i=0;i<1024;i++)
		{
			if(p->rfd_top->status)
				break;
			DELAY_16();
			if(i == 1023)
				printk("%s: RU hasn't fetched next RFD (not busy/complete)\n",dev->name);
		}
	}
#endif

#if 0
	if(!at_least_one)
	{
		int i;
		volatile struct rfd_struct *rfds=p->rfd_top;
//.........这里部分代码省略.........

/*
 *	This is where all X.25 information frames pass.
 *
 *      Returns the amount of user data bytes sent on success
 *      or a negative error code on failure.
 */
int x25_output(struct sock *sk, struct sk_buff *skb)
{
	struct sk_buff *skbn;
	unsigned char header[X25_EXT_MIN_LEN];
	int err, frontlen, len;
	int sent=0, noblock = X25_SKB_CB(skb)->flags & MSG_DONTWAIT;
	struct x25_sock *x25 = x25_sk(sk);
	int header_len = x25->neighbour->extended ? X25_EXT_MIN_LEN :
						    X25_STD_MIN_LEN;
	int max_len = x25_pacsize_to_bytes(x25->facilities.pacsize_out);

	if (skb->len - header_len > max_len) {
		/* Save a copy of the Header */
		skb_copy_from_linear_data(skb, header, header_len);
		skb_pull(skb, header_len);

		frontlen = skb_headroom(skb);

		while (skb->len > 0) {
			release_sock(sk);
			skbn = sock_alloc_send_skb(sk, frontlen + max_len,
						   noblock, &err);
			lock_sock(sk);
			if (!skbn) {
				if (err == -EWOULDBLOCK && noblock){
					kfree_skb(skb);
					return sent;
				}
				SOCK_DEBUG(sk, "x25_output: fragment alloc"
					       " failed, err=%d, %d bytes "
					       "sent\n", err, sent);
				return err;
			}

			skb_reserve(skbn, frontlen);

			len = max_len > skb->len ? skb->len : max_len;

			/* Copy the user data */
			skb_copy_from_linear_data(skb, skb_put(skbn, len), len);
			skb_pull(skb, len);

			/* Duplicate the Header */
			skb_push(skbn, header_len);
			skb_copy_to_linear_data(skbn, header, header_len);

			if (skb->len > 0) {
				if (x25->neighbour->extended)
					skbn->data[3] |= X25_EXT_M_BIT;
				else
					skbn->data[2] |= X25_STD_M_BIT;
			}

			skb_queue_tail(&sk->sk_write_queue, skbn);
			sent += len;
		}

		kfree_skb(skb);
	} else {
		skb_queue_tail(&sk->sk_write_queue, skb);
		sent = skb->len - header_len;
	}
	return sent;
}

static int
receive_packet (struct net_device *dev)
{
	struct netdev_private *np = netdev_priv(dev);
	int entry = np->cur_rx % RX_RING_SIZE;
	int cnt = 30;

	/*                                                                    */
	while (1) {
		struct netdev_desc *desc = &np->rx_ring[entry];
		int pkt_len;
		u64 frame_status;

		if (!(desc->status & cpu_to_le64(RFDDone)) ||
		    !(desc->status & cpu_to_le64(FrameStart)) ||
		    !(desc->status & cpu_to_le64(FrameEnd)))
			break;

		/*                     */
		frame_status = le64_to_cpu(desc->status);
		pkt_len = frame_status & 0xffff;
		if (--cnt < 0)
			break;
		/*                                          */
		if (frame_status & RFS_Errors) {
			np->stats.rx_errors++;
			if (frame_status & (RxRuntFrame | RxLengthError))
				np->stats.rx_length_errors++;
			if (frame_status & RxFCSError)
				np->stats.rx_crc_errors++;
			if (frame_status & RxAlignmentError && np->speed != 1000)
				np->stats.rx_frame_errors++;
			if (frame_status & RxFIFOOverrun)
	 			np->stats.rx_fifo_errors++;
		} else {
			struct sk_buff *skb;

			/*                                 */
			if (pkt_len > copy_thresh) {
				pci_unmap_single (np->pdev,
						  desc_to_dma(desc),
						  np->rx_buf_sz,
						  PCI_DMA_FROMDEVICE);
				skb_put (skb = np->rx_skbuff[entry], pkt_len);
				np->rx_skbuff[entry] = NULL;
			} else if ((skb = netdev_alloc_skb_ip_align(dev, pkt_len))) {
				pci_dma_sync_single_for_cpu(np->pdev,
							    desc_to_dma(desc),
							    np->rx_buf_sz,
							    PCI_DMA_FROMDEVICE);
				skb_copy_to_linear_data (skb,
						  np->rx_skbuff[entry]->data,
						  pkt_len);
				skb_put (skb, pkt_len);
				pci_dma_sync_single_for_device(np->pdev,
							       desc_to_dma(desc),
							       np->rx_buf_sz,
							       PCI_DMA_FROMDEVICE);
			}
			skb->protocol = eth_type_trans (skb, dev);
#if 0
			/*                                                  */
			if (np->pdev->pci_rev_id >= 0x0c &&
				!(frame_status & (TCPError | UDPError | IPError))) {
				skb->ip_summed = CHECKSUM_UNNECESSARY;
			}
#endif
			netif_rx (skb);
		}
		entry = (entry + 1) % RX_RING_SIZE;
	}
	spin_lock(&np->rx_lock);
	np->cur_rx = entry;
	/*                                                 */
	entry = np->old_rx;
	while (entry != np->cur_rx) {
		struct sk_buff *skb;
		/*                                           */
		if (np->rx_skbuff[entry] == NULL) {
			skb = netdev_alloc_skb_ip_align(dev, np->rx_buf_sz);
			if (skb == NULL) {
				np->rx_ring[entry].fraginfo = 0;
				printk (KERN_INFO
					"%s: receive_packet: "
					"Unable to re-allocate Rx skbuff.#%d\n",
					dev->name, entry);
				break;
			}
			np->rx_skbuff[entry] = skb;
			np->rx_ring[entry].fraginfo =
			    cpu_to_le64 (pci_map_single
					 (np->pdev, skb->data, np->rx_buf_sz,
					  PCI_DMA_FROMDEVICE));
		}
		np->rx_ring[entry].fraginfo |=
		    cpu_to_le64((u64)np->rx_buf_sz << 48);
		np->rx_ring[entry].status = 0;
		entry = (entry + 1) % RX_RING_SIZE;
	}
	np->old_rx = entry;
//.........这里部分代码省略.........

/* During a receive, the cur_rx points to the current incoming buffer.
 * When we update through the ring, if the next incoming buffer has
 * not been given to the system, we just set the empty indicator,
 * effectively tossing the packet.
 */
static int
scc_enet_rx(struct net_device *dev)
{
    struct	scc_enet_private *cep;
    volatile cbd_t	*bdp;
    struct	sk_buff *skb;
    ushort	pkt_len;

    cep = dev->priv;

    /* First, grab all of the stats for the incoming packet.
     * These get messed up if we get called due to a busy condition.
     */
    bdp = cep->cur_rx;

    for (;;) {
        if (bdp->cbd_sc & BD_ENET_RX_EMPTY)
            break;

#ifndef final_version
        /* Since we have allocated space to hold a complete frame, both
         * the first and last indicators should be set.
         */
        if ((bdp->cbd_sc & (BD_ENET_RX_FIRST | BD_ENET_RX_LAST)) !=
                (BD_ENET_RX_FIRST | BD_ENET_RX_LAST))
            printk("CPM ENET: rcv is not first+last\n");
#endif

        /* Frame too long or too short.
        */
        if (bdp->cbd_sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
            cep->stats.rx_length_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_NO)	/* Frame alignment */
            cep->stats.rx_frame_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_CR)	/* CRC Error */
            cep->stats.rx_crc_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_OV)	/* FIFO overrun */
            cep->stats.rx_crc_errors++;

        /* Report late collisions as a frame error.
         * On this error, the BD is closed, but we don't know what we
         * have in the buffer.  So, just drop this frame on the floor.
         */
        if (bdp->cbd_sc & BD_ENET_RX_CL) {
            cep->stats.rx_frame_errors++;
        }
        else {

            /* Process the incoming frame.
            */
            cep->stats.rx_packets++;
            pkt_len = bdp->cbd_datlen;
            cep->stats.rx_bytes += pkt_len;

            /* This does 16 byte alignment, much more than we need.
             * The packet length includes FCS, but we don't want to
             * include that when passing upstream as it messes up
             * bridging applications.
             */
            skb = dev_alloc_skb(pkt_len-4);

            if (skb == NULL) {
                printk("%s: Memory squeeze, dropping packet.\n", dev->name);
                cep->stats.rx_dropped++;
            }
            else {
                skb_put(skb,pkt_len-4);	/* Make room */
                skb_copy_to_linear_data(skb,
                                        (unsigned char *)__va(bdp->cbd_bufaddr),
                                        pkt_len-4);
                skb->protocol=eth_type_trans(skb,dev);
                netif_rx(skb);
            }
        }

        /* Clear the status flags for this buffer.
        */
        bdp->cbd_sc &= ~BD_ENET_RX_STATS;

        /* Mark the buffer empty.
        */
        bdp->cbd_sc |= BD_ENET_RX_EMPTY;

        /* Update BD pointer to next entry.
        */
        if (bdp->cbd_sc & BD_ENET_RX_WRAP)
            bdp = cep->rx_bd_base;
        else
            bdp++;

    }
    cep->cur_rx = (cbd_t *)bdp;

    return 0;
}

static int udp_uncompress(struct sk_buff *skb, size_t needed)
{
	u8 tmp = 0, val = 0;
	struct udphdr uh;
	bool fail;
	int err;

	fail = lowpan_fetch_skb(skb, &tmp, sizeof(tmp));

	pr_debug("UDP header uncompression\n");
	switch (tmp & LOWPAN_NHC_UDP_CS_P_11) {
	case LOWPAN_NHC_UDP_CS_P_00:
		fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source));
		fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest));
		break;
	case LOWPAN_NHC_UDP_CS_P_01:
		fail |= lowpan_fetch_skb(skb, &uh.source, sizeof(uh.source));
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.dest = htons(val + LOWPAN_NHC_UDP_8BIT_PORT);
		break;
	case LOWPAN_NHC_UDP_CS_P_10:
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.source = htons(val + LOWPAN_NHC_UDP_8BIT_PORT);
		fail |= lowpan_fetch_skb(skb, &uh.dest, sizeof(uh.dest));
		break;
	case LOWPAN_NHC_UDP_CS_P_11:
		fail |= lowpan_fetch_skb(skb, &val, sizeof(val));
		uh.source = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val >> 4));
		uh.dest = htons(LOWPAN_NHC_UDP_4BIT_PORT + (val & 0x0f));
		break;
	default:
		BUG();
	}

	pr_debug("uncompressed UDP ports: src = %d, dst = %d\n",
		 ntohs(uh.source), ntohs(uh.dest));

	/* checksum */
	if (tmp & LOWPAN_NHC_UDP_CS_C) {
		pr_debug_ratelimited("checksum elided currently not supported\n");
		fail = true;
	} else {
		fail |= lowpan_fetch_skb(skb, &uh.check, sizeof(uh.check));
	}

	if (fail)
		return -EINVAL;

	/* UDP length needs to be infered from the lower layers
	 * here, we obtain the hint from the remaining size of the
	 * frame
	 */
	uh.len = htons(skb->len + sizeof(struct udphdr));
	pr_debug("uncompressed UDP length: src = %d", ntohs(uh.len));

	/* replace the compressed UDP head by the uncompressed UDP
	 * header
	 */
	err = skb_cow(skb, needed);
	if (unlikely(err))
		return err;

	skb_push(skb, sizeof(struct udphdr));
	skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));

	return 0;
}

static void fifo_dma_copy_to_linear_skb(struct ccat_eth_fifo *const fifo,
					struct sk_buff *skb, const size_t len)
{
	skb_copy_to_linear_data(skb, fifo->dma.next->data, len);
}

static void pxa_irda_fir_irq_eif(struct pxa_irda *si, struct net_device *dev, int icsr0)
{
	unsigned int len, stat, data;

	
	len = DTADR(si->rxdma) - si->dma_rx_buff_phy;

	do {
		
		stat = ICSR1;
		rmb();
		data = ICDR;

		if (stat & (ICSR1_CRE | ICSR1_ROR)) {
			dev->stats.rx_errors++;
			if (stat & ICSR1_CRE) {
				printk(KERN_DEBUG "pxa_ir: fir receive CRC error\n");
				dev->stats.rx_crc_errors++;
			}
			if (stat & ICSR1_ROR) {
				printk(KERN_DEBUG "pxa_ir: fir receive overrun\n");
				dev->stats.rx_over_errors++;
			}
		} else	{
			si->dma_rx_buff[len++] = data;
		}
		
		if (stat & ICSR1_EOF)
			break;
	} while (ICSR0 & ICSR0_EIF);

	if (stat & ICSR1_EOF) {
		
		struct sk_buff *skb;

		if (icsr0 & ICSR0_FRE) {
			printk(KERN_ERR "pxa_ir: dropping erroneous frame\n");
			dev->stats.rx_dropped++;
			return;
		}

		skb = alloc_skb(len+1,GFP_ATOMIC);
		if (!skb)  {
			printk(KERN_ERR "pxa_ir: fir out of memory for receive skb\n");
			dev->stats.rx_dropped++;
			return;
		}

		
		skb_reserve(skb, 1);
		skb_copy_to_linear_data(skb, si->dma_rx_buff, len);
		skb_put(skb, len);

		
		skb->dev = dev;
		skb_reset_mac_header(skb);
		skb->protocol = htons(ETH_P_IRDA);
		netif_rx(skb);

		dev->stats.rx_packets++;
		dev->stats.rx_bytes += len;
	}
}

static int sendup_buffer (struct net_device *dev)
{
	/* on entry, command is in ltdmacbuf, data in ltdmabuf */
	/* called from idle, non-reentrant */

	int dnode, snode, llaptype, len; 
	int sklen;
	struct sk_buff *skb;
	struct lt_rcvlap *ltc = (struct lt_rcvlap *) ltdmacbuf;

	if (ltc->command != LT_RCVLAP) {
		printk("unknown command 0x%02x from ltpc card\n",ltc->command);
		return(-1);
	}
	dnode = ltc->dnode;
	snode = ltc->snode;
	llaptype = ltc->laptype;
	len = ltc->length; 

	sklen = len;
	if (llaptype == 1) 
		sklen += 8;  /* correct for short ddp */
	if(sklen > 800) {
		printk(KERN_INFO "%s: nonsense length in ltpc command 0x14: 0x%08x\n",
			dev->name,sklen);
		return -1;
	}

	if ( (llaptype==0) || (llaptype>2) ) {
		printk(KERN_INFO "%s: unknown LLAP type: %d\n",dev->name,llaptype);
		return -1;
	}


	skb = dev_alloc_skb(3+sklen);
	if (skb == NULL) 
	{
		printk("%s: dropping packet due to memory squeeze.\n",
			dev->name);
		return -1;
	}
	skb->dev = dev;

	if (sklen > len)
		skb_reserve(skb,8);
	skb_put(skb,len+3);
	skb->protocol = htons(ETH_P_LOCALTALK);
	/* add LLAP header */
	skb->data[0] = dnode;
	skb->data[1] = snode;
	skb->data[2] = llaptype;
	skb_reset_mac_header(skb);	/* save pointer to llap header */
	skb_pull(skb,3);

	/* copy ddp(s,e)hdr + contents */
	skb_copy_to_linear_data(skb, ltdmabuf, len);

	skb_reset_transport_header(skb);

	dev->stats.rx_packets++;
	dev->stats.rx_bytes += skb->len;

	/* toss it onwards */
	netif_rx(skb);
	return 0;
}

/*
 * Au1000 receive routine.
 */
static int au1000_rx(struct net_device *dev)
{
	struct au1000_private *aup = netdev_priv(dev);
	struct sk_buff *skb;
	volatile rx_dma_t *prxd;
	u32 buff_stat, status;
	db_dest_t *pDB;
	u32	frmlen;

	if (au1000_debug > 5)
		printk("%s: au1000_rx head %d\n", dev->name, aup->rx_head);

	prxd = aup->rx_dma_ring[aup->rx_head];
	buff_stat = prxd->buff_stat;
	while (buff_stat & RX_T_DONE)  {
		status = prxd->status;
		pDB = aup->rx_db_inuse[aup->rx_head];
		update_rx_stats(dev, status);
		if (!(status & RX_ERROR))  {

			/* good frame */
			frmlen = (status & RX_FRAME_LEN_MASK);
			frmlen -= 4; /* Remove FCS */
			skb = dev_alloc_skb(frmlen + 2);
			if (skb == NULL) {
				printk(KERN_ERR
				       "%s: Memory squeeze, dropping packet.\n",
				       dev->name);
				dev->stats.rx_dropped++;
				continue;
			}
			skb_reserve(skb, 2);	/* 16 byte IP header align */
			skb_copy_to_linear_data(skb,
				(unsigned char *)pDB->vaddr, frmlen);
			skb_put(skb, frmlen);
			skb->protocol = eth_type_trans(skb, dev);
			netif_rx(skb);	/* pass the packet to upper layers */
		}
		else {
			if (au1000_debug > 4) {
				if (status & RX_MISSED_FRAME)
					printk("rx miss\n");
				if (status & RX_WDOG_TIMER)
					printk("rx wdog\n");
				if (status & RX_RUNT)
					printk("rx runt\n");
				if (status & RX_OVERLEN)
					printk("rx overlen\n");
				if (status & RX_COLL)
					printk("rx coll\n");
				if (status & RX_MII_ERROR)
					printk("rx mii error\n");
				if (status & RX_CRC_ERROR)
					printk("rx crc error\n");
				if (status & RX_LEN_ERROR)
					printk("rx len error\n");
				if (status & RX_U_CNTRL_FRAME)
					printk("rx u control frame\n");
			}
		}
		prxd->buff_stat = (u32)(pDB->dma_addr | RX_DMA_ENABLE);
		aup->rx_head = (aup->rx_head + 1) & (NUM_RX_DMA - 1);
		au_sync();

		/* next descriptor */
		prxd = aup->rx_dma_ring[aup->rx_head];
		buff_stat = prxd->buff_stat;
	}
	return 0;
}

int vnic_rx_skb(struct vnic_login *login, struct vnic_rx_ring *ring,
		struct ib_wc *wc, int ip_summed, char *eth_hdr_va)
{
	u64 wr_id = (unsigned int)wc->wr_id;
	struct sk_buff *skb;
	int used_frags;
	char *va = eth_hdr_va;
	int length = wc->byte_len - VNIC_EOIB_HDR_SIZE - VNIC_VLAN_OFFSET(login),
	    linear_length = (length <= SMALL_PACKET_SIZE) ?
	    length : SMALL_PACKET_SIZE, hdr_len = min(length, HEADER_COPY_SIZE),
	    offest = NET_IP_ALIGN + 16;
	struct ib_device *ib_dev = login->port->dev->ca;

	/* alloc a small linear SKB */
	skb = alloc_skb(linear_length + offest, GFP_ATOMIC);
	if (unlikely(!skb))
		return -ENOMEM;

	skb_record_rx_queue(skb, ring->index);
	skb_reserve(skb, offest);

	if (vnic_linear_small_pkt && length <= SMALL_PACKET_SIZE) {
		u64 dma;

		/* We are copying all relevant data to the skb - temporarily
		 * synch buffers for the copy
		 */
		dma = ring->rx_info[wr_id].dma_addr[0] + VNIC_EOIB_HDR_SIZE +
			VNIC_VLAN_OFFSET(login);
		ib_dma_sync_single_for_cpu(ib_dev, dma, length,
					   DMA_FROM_DEVICE);
		skb_copy_to_linear_data(skb, va, length);
		ib_dma_sync_single_for_device(ib_dev, dma, length,
					      DMA_FROM_DEVICE);
		skb->tail += length;
	} else {
		/* unmap the needed fragmentand reallocate them. Fragments that
		 * were not used will not be reused as is. */
		used_frags = vnic_unmap_and_replace_rx(ring, ib_dev,
						       skb_shinfo(skb)->frags,
						       wr_id, wc->byte_len);
		if (!used_frags)
			goto free_and_repost;

		skb_shinfo(skb)->nr_frags = used_frags;

		/* Copy headers into the skb linear buffer */
		memcpy(skb->data, va, hdr_len);
		skb->tail += hdr_len;
		/* Skip headers in first fragment */
		skb_shinfo(skb)->frags[0].page_offset +=
		    (VNIC_EOIB_HDR_SIZE + VNIC_VLAN_OFFSET(login) +
		     hdr_len);

		/* Adjust size of first fragment */
		skb_shinfo(skb)->frags[0].size -=
		    (VNIC_EOIB_HDR_SIZE + VNIC_VLAN_OFFSET(login) +
		     hdr_len);
		skb->data_len = length - hdr_len;
	}

	/* update skb fields */
	skb->len = length;
	skb->truesize = length + sizeof(struct sk_buff);
	skb->ip_summed = ip_summed;
	skb->dev = login->dev;
	skb->protocol = eth_type_trans(skb, skb->dev);

	return vnic_rx(login, skb, wc);

free_and_repost:
	dev_kfree_skb(skb);
	return -ENODEV;

}

static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ipcomp_data *ipcd = x->data;
	const int plen = skb->len;
	int dlen = IPCOMP_SCRATCH_SIZE;
	const u8 *start = skb->data;
	const int cpu = get_cpu();
	u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
	struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu);
	int err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen);
	int len;

	if (err)
		goto out;

	if (dlen < (plen + sizeof(struct ip_comp_hdr))) {
		err = -EINVAL;
		goto out;
	}

	len = dlen - plen;
	if (len > skb_tailroom(skb))
		len = skb_tailroom(skb);

	__skb_put(skb, len);

	len += plen;
	skb_copy_to_linear_data(skb, scratch, len);

	while ((scratch += len, dlen -= len) > 0) {
		skb_frag_t *frag;
		struct page *page;

		err = -EMSGSIZE;
		if (WARN_ON(skb_shinfo(skb)->nr_frags >= MAX_SKB_FRAGS))
			goto out;

		frag = skb_shinfo(skb)->frags + skb_shinfo(skb)->nr_frags;
		page = alloc_page(GFP_ATOMIC);

		err = -ENOMEM;
		if (!page)
			goto out;

		__skb_frag_set_page(frag, page);

		len = PAGE_SIZE;
		if (dlen < len)
			len = dlen;

		frag->page_offset = 0;
		skb_frag_size_set(frag, len);
		memcpy(skb_frag_address(frag), scratch, len);

		skb->truesize += len;
		skb->data_len += len;
		skb->len += len;

		skb_shinfo(skb)->nr_frags++;
	}

	err = 0;

out:
	put_cpu();
	return err;
}

/* Transmit routine used by generic_netmap_txsync(). Returns 0 on success
   and -1 on error (which may be packet drops or other errors). */
int
nm_os_generic_xmit_frame(struct nm_os_gen_arg *a)
{
	struct mbuf *m = a->m;
	struct ifnet *ifp = a->ifp;
	u_int len = a->len;
	netdev_tx_t ret;

	/* We know that the driver needs to prepend ifp->needed_headroom bytes
	 * to each packet to be transmitted. We then reset the mbuf pointers
	 * to the correct initial state:
	 *    ___________________________________________
	 *    ^           ^                             ^
	 *    |           |                             |
	 *   head        data                          end
	 *               tail
	 *
	 * which correspond to an empty buffer with exactly
	 * ifp->needed_headroom bytes between head and data.
	 */
	m->len = 0;
	m->data = m->head + ifp->needed_headroom;
	skb_reset_tail_pointer(m);
	skb_reset_mac_header(m);
	skb_reset_network_header(m);

	/* Copy a netmap buffer into the mbuf.
	 * TODO Support the slot flags (NS_MOREFRAG, NS_INDIRECT). */
	skb_copy_to_linear_data(m, a->addr, len); // skb_store_bits(m, 0, addr, len);
	skb_put(m, len);

	/* Hold a reference on this, we are going to recycle mbufs as
	 * much as possible. */
	NM_ATOMIC_INC(&m->users);

	/* On linux m->dev is not reliable, since it can be changed by the
	 * ndo_start_xmit() callback. This happens, for instance, with veth
	 * and bridge drivers. For this reason, the nm_os_generic_xmit_frame()
	 * implementation for linux stores a copy of m->dev into the
	 * destructor_arg field. */
	m->dev = ifp;
	skb_shinfo(m)->destructor_arg = m->dev;

	/* Tell generic_ndo_start_xmit() to pass this mbuf to the driver. */
	skb_set_queue_mapping(m, a->ring_nr);
	m->priority = a->qevent ? NM_MAGIC_PRIORITY_TXQE : NM_MAGIC_PRIORITY_TX;

	ret = dev_queue_xmit(m);

	if (unlikely(ret != NET_XMIT_SUCCESS)) {
		/* Reset priority, so that generic_netmap_tx_clean() can
		 * reclaim this mbuf. */
		m->priority = 0;

		/* Qdisc queue is full (this cannot happen with
		 * the netmap-aware qdisc, see exaplanation in
		 * netmap_generic_txsync), or qdisc is being
		 * deactivated. In the latter case dev_queue_xmit()
		 * does not call the enqueue method and returns
		 * NET_XMIT_DROP.
		 * If there is no carrier, the generic qdisc is
		 * not yet active (is pending in the qdisc_sleeping
		 * field), and so the temporary noop qdisc enqueue
		 * method will drop the packet and return NET_XMIT_CN.
		 */
		RD(3, "Warning: dev_queue_xmit() is dropping [%d]", ret);
		return -1;
	}

	return 0;
}

/** Routine to push packets arriving on Octeon interface upto network layer.
 * @param oct_id   - octeon device id.
 * @param skbuff   - skbuff struct to be passed to network layer.
 * @param len      - size of total data received.
 * @param rh       - Control header associated with the packet
 * @param param    - additional control data with the packet
 * @param arg      - farg registered in droq_ops
 */
static void
liquidio_push_packet(u32 octeon_id __attribute__((unused)),
		     void *skbuff,
		     u32 len,
		     union octeon_rh *rh,
		     void *param,
		     void *arg)
{
	struct net_device *netdev = (struct net_device *)arg;
	struct octeon_droq *droq =
	    container_of(param, struct octeon_droq, napi);
	struct sk_buff *skb = (struct sk_buff *)skbuff;
	struct skb_shared_hwtstamps *shhwtstamps;
	struct napi_struct *napi = param;
	u16 vtag = 0;
	u32 r_dh_off;
	u64 ns;

	if (netdev) {
		struct lio *lio = GET_LIO(netdev);
		struct octeon_device *oct = lio->oct_dev;

		/* Do not proceed if the interface is not in RUNNING state. */
		if (!ifstate_check(lio, LIO_IFSTATE_RUNNING)) {
			recv_buffer_free(skb);
			droq->stats.rx_dropped++;
			return;
		}

		skb->dev = netdev;

		skb_record_rx_queue(skb, droq->q_no);
		if (likely(len > MIN_SKB_SIZE)) {
			struct octeon_skb_page_info *pg_info;
			unsigned char *va;

			pg_info = ((struct octeon_skb_page_info *)(skb->cb));
			if (pg_info->page) {
				/* For Paged allocation use the frags */
				va = page_address(pg_info->page) +
					pg_info->page_offset;
				memcpy(skb->data, va, MIN_SKB_SIZE);
				skb_put(skb, MIN_SKB_SIZE);
				skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
						pg_info->page,
						pg_info->page_offset +
						MIN_SKB_SIZE,
						len - MIN_SKB_SIZE,
						LIO_RXBUFFER_SZ);
			}
		} else {
			struct octeon_skb_page_info *pg_info =
				((struct octeon_skb_page_info *)(skb->cb));
			skb_copy_to_linear_data(skb, page_address(pg_info->page)
						+ pg_info->page_offset, len);
			skb_put(skb, len);
			put_page(pg_info->page);
		}

		r_dh_off = (rh->r_dh.len - 1) * BYTES_PER_DHLEN_UNIT;

		if (oct->ptp_enable) {
			if (rh->r_dh.has_hwtstamp) {
				/* timestamp is included from the hardware at
				 * the beginning of the packet.
				 */
				if (ifstate_check
					(lio,
					 LIO_IFSTATE_RX_TIMESTAMP_ENABLED)) {
					/* Nanoseconds are in the first 64-bits
					 * of the packet.
					 */
					memcpy(&ns, (skb->data + r_dh_off),
					       sizeof(ns));
					r_dh_off -= BYTES_PER_DHLEN_UNIT;
					shhwtstamps = skb_hwtstamps(skb);
					shhwtstamps->hwtstamp =
						ns_to_ktime(ns +
							    lio->ptp_adjust);
				}
			}
		}

		if (rh->r_dh.has_hash) {
			__be32 *hash_be = (__be32 *)(skb->data + r_dh_off);
			u32 hash = be32_to_cpu(*hash_be);

			skb_set_hash(skb, hash, PKT_HASH_TYPE_L4);
			r_dh_off -= BYTES_PER_DHLEN_UNIT;
		}

		skb_pull(skb, rh->r_dh.len * BYTES_PER_DHLEN_UNIT);
//.........这里部分代码省略.........