alistair23-linux/drivers/staging/bcm/Bcmnet.c
Jason Wang f663dd9aaf net: core: explicitly select a txq before doing l2 forwarding
Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 13:23:08 -05:00

242 lines
6.2 KiB
C

#include "headers.h"
struct net_device *gblpnetdev;
static INT bcm_open(struct net_device *dev)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
if (Adapter->fw_download_done == false) {
pr_notice(PFX "%s: link up failed (download in progress)\n",
dev->name);
return -EBUSY;
}
if (netif_msg_ifup(Adapter))
pr_info(PFX "%s: enabling interface\n", dev->name);
if (Adapter->LinkUpStatus) {
if (netif_msg_link(Adapter))
pr_info(PFX "%s: link up\n", dev->name);
netif_carrier_on(Adapter->dev);
netif_start_queue(Adapter->dev);
}
return 0;
}
static INT bcm_close(struct net_device *dev)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
if (netif_msg_ifdown(Adapter))
pr_info(PFX "%s: disabling interface\n", dev->name);
netif_carrier_off(dev);
netif_stop_queue(dev);
return 0;
}
static u16 bcm_select_queue(struct net_device *dev, struct sk_buff *skb,
void *accel_priv)
{
return ClassifyPacket(netdev_priv(dev), skb);
}
/*******************************************************************
* Function - bcm_transmit()
*
* Description - This is the main transmit function for our virtual
* interface(eth0). It handles the ARP packets. It
* clones this packet and then Queue it to a suitable
* Queue. Then calls the transmit_packet().
*
* Parameter - skb - Pointer to the socket buffer structure
* dev - Pointer to the virtual net device structure
*
*********************************************************************/
static netdev_tx_t bcm_transmit(struct sk_buff *skb, struct net_device *dev)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
u16 qindex = skb_get_queue_mapping(skb);
if (Adapter->device_removed || !Adapter->LinkUpStatus)
goto drop;
if (Adapter->TransferMode != IP_PACKET_ONLY_MODE)
goto drop;
if (INVALID_QUEUE_INDEX == qindex)
goto drop;
if (Adapter->PackInfo[qindex].uiCurrentPacketsOnHost >=
SF_MAX_ALLOWED_PACKETS_TO_BACKUP)
return NETDEV_TX_BUSY;
/* Now Enqueue the packet */
if (netif_msg_tx_queued(Adapter))
pr_info(PFX "%s: enqueueing packet to queue %d\n",
dev->name, qindex);
spin_lock(&Adapter->PackInfo[qindex].SFQueueLock);
Adapter->PackInfo[qindex].uiCurrentBytesOnHost += skb->len;
Adapter->PackInfo[qindex].uiCurrentPacketsOnHost++;
*((B_UINT32 *) skb->cb + SKB_CB_LATENCY_OFFSET) = jiffies;
ENQUEUEPACKET(Adapter->PackInfo[qindex].FirstTxQueue,
Adapter->PackInfo[qindex].LastTxQueue, skb);
atomic_inc(&Adapter->TotalPacketCount);
spin_unlock(&Adapter->PackInfo[qindex].SFQueueLock);
/* FIXME - this is racy and incorrect, replace with work queue */
if (!atomic_read(&Adapter->TxPktAvail)) {
atomic_set(&Adapter->TxPktAvail, 1);
wake_up(&Adapter->tx_packet_wait_queue);
}
return NETDEV_TX_OK;
drop:
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
/**
@ingroup init_functions
Register other driver entry points with the kernel
*/
static const struct net_device_ops bcmNetDevOps = {
.ndo_open = bcm_open,
.ndo_stop = bcm_close,
.ndo_start_xmit = bcm_transmit,
.ndo_change_mtu = eth_change_mtu,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
.ndo_select_queue = bcm_select_queue,
};
static struct device_type wimax_type = {
.name = "wimax",
};
static int bcm_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
cmd->supported = 0;
cmd->advertising = 0;
cmd->speed = SPEED_10000;
cmd->duplex = DUPLEX_FULL;
cmd->port = PORT_TP;
cmd->phy_address = 0;
cmd->transceiver = XCVR_INTERNAL;
cmd->autoneg = AUTONEG_DISABLE;
cmd->maxtxpkt = 0;
cmd->maxrxpkt = 0;
return 0;
}
static void bcm_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
struct bcm_interface_adapter *psIntfAdapter =
Adapter->pvInterfaceAdapter;
struct usb_device *udev = interface_to_usbdev(psIntfAdapter->interface);
strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
strlcpy(info->version, DRV_VERSION, sizeof(info->version));
snprintf(info->fw_version, sizeof(info->fw_version), "%u.%u",
Adapter->uiFlashLayoutMajorVersion,
Adapter->uiFlashLayoutMinorVersion);
usb_make_path(udev, info->bus_info, sizeof(info->bus_info));
}
static u32 bcm_get_link(struct net_device *dev)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
return Adapter->LinkUpStatus;
}
static u32 bcm_get_msglevel(struct net_device *dev)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
return Adapter->msg_enable;
}
static void bcm_set_msglevel(struct net_device *dev, u32 level)
{
struct bcm_mini_adapter *Adapter = GET_BCM_ADAPTER(dev);
Adapter->msg_enable = level;
}
static const struct ethtool_ops bcm_ethtool_ops = {
.get_settings = bcm_get_settings,
.get_drvinfo = bcm_get_drvinfo,
.get_link = bcm_get_link,
.get_msglevel = bcm_get_msglevel,
.set_msglevel = bcm_set_msglevel,
};
int register_networkdev(struct bcm_mini_adapter *Adapter)
{
struct net_device *net = Adapter->dev;
struct bcm_interface_adapter *IntfAdapter = Adapter->pvInterfaceAdapter;
struct usb_interface *udev = IntfAdapter->interface;
struct usb_device *xdev = IntfAdapter->udev;
int result;
net->netdev_ops = &bcmNetDevOps;
net->ethtool_ops = &bcm_ethtool_ops;
net->mtu = MTU_SIZE; /* 1400 Bytes */
net->tx_queue_len = TX_QLEN;
net->flags |= IFF_NOARP;
netif_carrier_off(net);
SET_NETDEV_DEVTYPE(net, &wimax_type);
/* Read the MAC Address from EEPROM */
result = ReadMacAddressFromNVM(Adapter);
if (result != STATUS_SUCCESS) {
dev_err(&udev->dev,
PFX "Error in Reading the mac Address: %d", result);
return -EIO;
}
result = register_netdev(net);
if (result)
return result;
gblpnetdev = Adapter->dev;
if (netif_msg_probe(Adapter))
dev_info(&udev->dev, PFX "%s: register usb-%s-%s %pM\n",
net->name, xdev->bus->bus_name, xdev->devpath,
net->dev_addr);
return 0;
}
void unregister_networkdev(struct bcm_mini_adapter *Adapter)
{
struct net_device *net = Adapter->dev;
struct bcm_interface_adapter *IntfAdapter = Adapter->pvInterfaceAdapter;
struct usb_interface *udev = IntfAdapter->interface;
struct usb_device *xdev = IntfAdapter->udev;
if (netif_msg_probe(Adapter))
dev_info(&udev->dev, PFX "%s: unregister usb-%s%s\n",
net->name, xdev->bus->bus_name, xdev->devpath);
unregister_netdev(Adapter->dev);
}