From: Anton Blanchard <anton@samba•org>
To: brking@linux•vnet.ibm.com, santil@linux•vnet.ibm.com
Cc: netdev@vger•kernel.org
Subject: [patch 07/20] ibmveth: Add scatter-gather support
Date: Mon, 23 Aug 2010 10:09:37 +1000 [thread overview]
Message-ID: <20100823001238.941872212@samba.org> (raw)
In-Reply-To: 20100823000930.546065833@samba.org
[-- Attachment #1: veth_sg --]
[-- Type: text/plain, Size: 7673 bytes --]
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: Anton Blanchard <anton@samba•org>
---
Index: net-next-2.6/drivers/net/ibmveth.c
===================================================================
--- net-next-2.6.orig/drivers/net/ibmveth.c 2010-08-23 08:52:30.283755038 +1000
+++ net-next-2.6/drivers/net/ibmveth.c 2010-08-23 08:52:30.633730198 +1000
@@ -897,6 +897,7 @@ static const struct ethtool_ops netdev_e
.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_devi
#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--));
+ descs[0].fields.flags_len = desc_flags | skb->len;
+ descs[0].fields.address = adapter->bounce_buffer_dma;
- 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++;
+ 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(struc
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);
next prev parent reply other threads:[~2010-08-23 0:28 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-23 0:09 [patch 00/20] ibmveth update Anton Blanchard
2010-08-23 0:09 ` [patch 01/20] ibmveth: Remove integer divide caused by modulus Anton Blanchard
2010-08-23 0:09 ` [patch 02/20] ibmveth: batch rx buffer replacement Anton Blanchard
2010-08-23 0:09 ` [patch 03/20] ibmveth: Remove LLTX Anton Blanchard
2010-08-23 0:09 ` [patch 04/20] ibmveth: Add tx_copybreak Anton Blanchard
2010-08-23 0:09 ` [patch 05/20] ibmveth: Add rx_copybreak Anton Blanchard
2010-08-23 0:09 ` [patch 06/20] ibmveth: Use lighter weight read memory barrier in ibmveth_poll Anton Blanchard
2010-08-23 0:09 ` Anton Blanchard [this message]
2010-08-23 0:09 ` [patch 08/20] ibmveth: Dont overallocate buffers Anton Blanchard
2010-08-23 20:49 ` Robert Jennings
2010-08-25 13:44 ` Brian King
2010-08-23 0:09 ` [patch 09/20] ibmveth: Add optional flush of rx buffer Anton Blanchard
2010-08-23 0:09 ` [patch 10/20] ibmveth: remove procfs code Anton Blanchard
2010-08-23 0:09 ` [patch 11/20] ibmveth: Convert to netdev_alloc_skb Anton Blanchard
2010-08-23 0:09 ` [patch 12/20] ibmveth: Remove redundant function prototypes Anton Blanchard
2010-08-23 0:09 ` [patch 13/20] ibmveth: Convert driver specific debug to netdev_dbg Anton Blanchard
2010-08-23 0:09 ` [patch 14/20] ibmveth: Convert driver specific error functions to netdev_err Anton Blanchard
2010-08-23 0:09 ` [patch 15/20] ibmveth: Some formatting fixes Anton Blanchard
2010-08-23 0:09 ` [patch 16/20] ibmveth: Coding style fixes Anton Blanchard
2010-08-23 0:09 ` [patch 17/20] ibmveth: Return -EINVAL on all ->probe errors Anton Blanchard
2010-08-23 0:09 ` [patch 18/20] ibmveth: Convert driver specific assert to BUG_ON Anton Blanchard
2010-08-23 0:09 ` [patch 19/20] ibmveth: Remove some unnecessary include files Anton Blanchard
2010-08-23 0:09 ` [patch 20/20] ibmveth: Update module information and version Anton Blanchard
2010-08-23 1:57 ` [patch 00/20] ibmveth update David Miller
2010-08-23 2:07 ` Anton Blanchard
2010-08-23 2:15 ` David Miller
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