Commit 6e8ab30e authored by Santiago Leon's avatar Santiago Leon Committed by David S. Miller
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ibmveth: Add scatter-gather support



ibmveth can scatter gather up to 6 segments. If we go over this then
we have no option but to call skb_linearize, like other drivers with
similar limitations do.
Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
Signed-off-by: default avatarSantiago Leon <santil@linux.vnet.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f89e49e7
......@@ -897,6 +897,7 @@ static const struct ethtool_ops netdev_ethtool_ops = {
.get_strings = ibmveth_get_strings,
.get_sset_count = ibmveth_get_sset_count,
.get_ethtool_stats = ibmveth_get_ethtool_stats,
.set_sg = ethtool_op_set_sg,
};
static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
......@@ -906,96 +907,158 @@ static int ibmveth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
#define page_offset(v) ((unsigned long)(v) & ((1 << 12) - 1))
static netdev_tx_t ibmveth_start_xmit(struct sk_buff *skb,
struct net_device *netdev)
static int ibmveth_send(struct ibmveth_adapter *adapter,
union ibmveth_buf_desc *descs)
{
struct ibmveth_adapter *adapter = netdev_priv(netdev);
union ibmveth_buf_desc desc;
unsigned long lpar_rc;
unsigned long correlator;
unsigned int retry_count;
unsigned int tx_dropped = 0;
unsigned int tx_bytes = 0;
unsigned int tx_packets = 0;
unsigned int tx_send_failed = 0;
unsigned int tx_map_failed = 0;
int used_bounce = 0;
unsigned long data_dma_addr;
unsigned long ret;
/*
* The retry count sets a maximum for the number of broadcast and
* multicast destinations within the system.
*/
retry_count = 1024;
correlator = 0;
do {
ret = h_send_logical_lan(adapter->vdev->unit_address,
descs[0].desc, descs[1].desc,
descs[2].desc, descs[3].desc,
descs[4].desc, descs[5].desc,
correlator, &correlator);
} while ((ret == H_BUSY) && (retry_count--));
if (ret != H_SUCCESS && ret != H_DROPPED) {
ibmveth_error_printk("tx: h_send_logical_lan failed with "
"rc=%ld\n", ret);
return 1;
}
return 0;
}
desc.fields.flags_len = IBMVETH_BUF_VALID | skb->len;
static netdev_tx_t ibmveth_start_xmit(struct sk_buff *skb,
struct net_device *netdev)
{
struct ibmveth_adapter *adapter = netdev_priv(netdev);
unsigned int desc_flags;
union ibmveth_buf_desc descs[6];
int last, i;
int force_bounce = 0;
/*
* veth handles a maximum of 6 segments including the header, so
* we have to linearize the skb if there are more than this.
*/
if (skb_shinfo(skb)->nr_frags > 5 && __skb_linearize(skb)) {
netdev->stats.tx_dropped++;
goto out;
}
/* veth can't checksum offload UDP */
if (skb->ip_summed == CHECKSUM_PARTIAL &&
ip_hdr(skb)->protocol != IPPROTO_TCP && skb_checksum_help(skb)) {
ibmveth_error_printk("tx: failed to checksum packet\n");
tx_dropped++;
netdev->stats.tx_dropped++;
goto out;
}
desc_flags = IBMVETH_BUF_VALID;
if (skb->ip_summed == CHECKSUM_PARTIAL) {
unsigned char *buf = skb_transport_header(skb) + skb->csum_offset;
unsigned char *buf = skb_transport_header(skb) +
skb->csum_offset;
desc.fields.flags_len |= (IBMVETH_BUF_NO_CSUM | IBMVETH_BUF_CSUM_GOOD);
desc_flags |= (IBMVETH_BUF_NO_CSUM | IBMVETH_BUF_CSUM_GOOD);
/* Need to zero out the checksum */
buf[0] = 0;
buf[1] = 0;
}
if (skb->len < tx_copybreak) {
used_bounce = 1;
} else {
data_dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
skb->len, DMA_TO_DEVICE);
if (dma_mapping_error(&adapter->vdev->dev, data_dma_addr)) {
if (!firmware_has_feature(FW_FEATURE_CMO))
ibmveth_error_printk("tx: unable to map "
"xmit buffer\n");
tx_map_failed++;
used_bounce = 1;
}
}
retry_bounce:
memset(descs, 0, sizeof(descs));
if (used_bounce) {
/*
* If a linear packet is below the rx threshold then
* copy it into the static bounce buffer. This avoids the
* cost of a TCE insert and remove.
*/
if (force_bounce || (!skb_is_nonlinear(skb) &&
(skb->len < tx_copybreak))) {
skb_copy_from_linear_data(skb, adapter->bounce_buffer,
skb->len);
desc.fields.address = adapter->bounce_buffer_dma;
} else
desc.fields.address = data_dma_addr;
/* send the frame. Arbitrarily set retrycount to 1024 */
correlator = 0;
retry_count = 1024;
do {
lpar_rc = h_send_logical_lan(adapter->vdev->unit_address,
desc.desc, 0, 0, 0, 0, 0,
correlator, &correlator);
} while ((lpar_rc == H_BUSY) && (retry_count--));
if(lpar_rc != H_SUCCESS && lpar_rc != H_DROPPED) {
ibmveth_error_printk("tx: h_send_logical_lan failed with rc=%ld\n", lpar_rc);
ibmveth_error_printk("tx: valid=%d, len=%d, address=0x%08x\n",
(desc.fields.flags_len & IBMVETH_BUF_VALID) ? 1 : 0,
skb->len, desc.fields.address);
tx_send_failed++;
tx_dropped++;
descs[0].fields.flags_len = desc_flags | skb->len;
descs[0].fields.address = adapter->bounce_buffer_dma;
if (ibmveth_send(adapter, descs)) {
adapter->tx_send_failed++;
netdev->stats.tx_dropped++;
} else {
netdev->stats.tx_packets++;
netdev->stats.tx_bytes += skb->len;
}
goto out;
}
/* Map the header */
descs[0].fields.address = dma_map_single(&adapter->vdev->dev, skb->data,
skb_headlen(skb),
DMA_TO_DEVICE);
if (dma_mapping_error(&adapter->vdev->dev, descs[0].fields.address))
goto map_failed;
descs[0].fields.flags_len = desc_flags | skb_headlen(skb);
/* Map the frags */
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
unsigned long dma_addr;
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
dma_addr = dma_map_page(&adapter->vdev->dev, frag->page,
frag->page_offset, frag->size,
DMA_TO_DEVICE);
if (dma_mapping_error(&adapter->vdev->dev, dma_addr))
goto map_failed_frags;
descs[i+1].fields.flags_len = desc_flags | frag->size;
descs[i+1].fields.address = dma_addr;
}
if (ibmveth_send(adapter, descs)) {
adapter->tx_send_failed++;
netdev->stats.tx_dropped++;
} else {
tx_packets++;
tx_bytes += skb->len;
netdev->stats.tx_packets++;
netdev->stats.tx_bytes += skb->len;
}
if (!used_bounce)
dma_unmap_single(&adapter->vdev->dev, data_dma_addr,
skb->len, DMA_TO_DEVICE);
for (i = 0; i < skb_shinfo(skb)->nr_frags + 1; i++)
dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
DMA_TO_DEVICE);
out:
netdev->stats.tx_dropped += tx_dropped;
netdev->stats.tx_bytes += tx_bytes;
netdev->stats.tx_packets += tx_packets;
adapter->tx_send_failed += tx_send_failed;
adapter->tx_map_failed += tx_map_failed;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
map_failed_frags:
last = i+1;
for (i = 0; i < last; i++)
dma_unmap_page(&adapter->vdev->dev, descs[i].fields.address,
descs[i].fields.flags_len & IBMVETH_BUF_LEN_MASK,
DMA_TO_DEVICE);
map_failed:
if (!firmware_has_feature(FW_FEATURE_CMO))
ibmveth_error_printk("tx: unable to map xmit buffer\n");
adapter->tx_map_failed++;
skb_linearize(skb);
force_bounce = 1;
goto retry_bounce;
}
static int ibmveth_poll(struct napi_struct *napi, int budget)
......@@ -1316,6 +1379,7 @@ static int __devinit ibmveth_probe(struct vio_dev *dev, const struct vio_device_
netdev->netdev_ops = &ibmveth_netdev_ops;
netdev->ethtool_ops = &netdev_ethtool_ops;
SET_NETDEV_DEV(netdev, &dev->dev);
netdev->features |= NETIF_F_SG;
memcpy(netdev->dev_addr, &adapter->mac_addr, netdev->addr_len);
......
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