[dpdk-dev] [PATCH v5] drivers/net:new PMD using tun/tap host interface

[Ferruh Yigit]

On 10/11/2016 10:51 PM, Keith Wiles wrote:
> The rte_eth_tap.c PMD creates a device using TUN/TAP interfaces
> on the local host. The PMD allows for DPDK and the host to
> communicate using a raw device interface on the host and in
> the DPDK application. The device created is a Tap device with
> a L2 packet header.
> 
> v5 - merge in changes from list review see related emails.
>      fixed checkpatch issues and many minor edits
> v4 - merge with latest driver changes
> v3 - fix includes by removing ifdef for other type besides Linux.
>      Fix the copyright notice in the Makefile
> v2 - merge all of the patches into one patch.
>      Fix a typo on naming the tap device.
>      Update the maintainers list
> 
> Signed-off-by: Keith Wiles <keith.wiles at intel.com>
> ---

<..>

> diff --git a/config/common_base b/config/common_base
> index f5d2eff..356c631 100644
> --- a/config/common_base
> +++ b/config/common_base
> @@ -592,3 +592,8 @@ CONFIG_RTE_APP_TEST_RESOURCE_TAR=n
>  CONFIG_RTE_TEST_PMD=y
>  CONFIG_RTE_TEST_PMD_RECORD_CORE_CYCLES=n
>  CONFIG_RTE_TEST_PMD_RECORD_BURST_STATS=n
> +
> +#
> +# Set TAP PMD to 'n' as it is only supported in Linux for now.

This comments moved to final .config and creates confusion, can we
remove it if you don't have a strong option to keep it?

<..>

> diff --git a/doc/guides/nics/tap.rst b/doc/guides/nics/tap.rst
> new file mode 100644
> index 0000000..eed81ec
> --- /dev/null
> +++ b/doc/guides/nics/tap.rst

<..>

> +.. code-block:: console
> +
> +   The interfaced name can be changed by adding the iface=foo0
> +   e.g. --vdev=eth_tap,iface=foo0 --vdev=eth_tap,iface=foo1, ...

For all file:
%s/eth_tap/net_tap/g, there are multiple lines with this usage


<..>

> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> new file mode 100644
> index 0000000..c13aa1b
> --- /dev/null
> +++ b/drivers/net/tap/rte_eth_tap.c

<..>

> +
> +struct tap_info {
> +	char name[RTE_ETH_NAME_MAX_LEN]; /* Interface name supplied/given */
> +	int speed;			 /* Speed of interface */
> +};

This struct can go away, it is not used, since with the updated code
rte_pmd_tap_probe() used tap_name and speed as seperate variables
instead of struct.


<..>

> +
> +	/* If the name is different that new name as default */
> +	if (name && strcmp(name, ifr.ifr_name))
> +		snprintf(name, RTE_ETH_NAME_MAX_LEN-1, "%s", ifr.ifr_name);

syntax, space around "-"

<..>

> +
> +static void
> +tap_stats_get(struct rte_eth_dev *dev, struct rte_eth_stats *tap_stats)
> +{
> +	unsigned i, imax;

checkpatch complain about not using "unsigned int"


<..>

> +static int
> +tap_setup_queue(struct rte_eth_dev *dev,
> +		struct pmd_internals *internals,
> +		uint16_t qid)
> +{
> +	struct rx_queue *rx = &internals->rxq[qid];
> +	struct tx_queue *tx = &internals->txq[qid];
> +	int fd;
> +
> +	if ((fd = rx->fd) < 0)
> +		if ((fd = tx->fd) < 0) {
> +			RTE_LOG(INFO, PMD, "Add queue to TAP %s for qid %d\n",
> +				dev->data->name, qid);
> +			if ((fd = tun_alloc(dev->data->name)) < 0) {

checkpatch complain about assignment in the if condition


<..>

> +	/* Now get the space available for data in the mbuf */
> +	buf_size = (uint16_t) (rte_pktmbuf_data_room_size(mp) -

syntax, no space after cast


<..>

> +	/* Create the first Tap device */
> +	if ((fd = tun_alloc(tap_name)) < 0) {

checkpatch complains about assignment in if condition

> +		RTE_LOG(ERR, PMD, "tun_alloc(%s) failed\n", dev->data->name);
> +		rte_free(pmd);

rte_free(data) or goto error_exit; ?

> +		rte_eth_dev_release_port(dev);
> +		return -EINVAL;
> +	}
> +
> +	/* Presetup the fds to -1 as being not working */
> +	for(i = 0; i < RTE_PMD_TAP_MAX_QUEUES; i++) {
> +		pmd->fds[i] = -1;
> +		pmd->rxq[i].fd = -1;
> +		pmd->txq[i].fd = -1;
> +	}
> +
> +	/* Take the TUN/TAP fd and place in the first location */
> +	pmd->rxq[0].fd = fd;
> +	pmd->txq[0].fd = fd;
> +	pmd->fds[0] = fd;
> +
> +	if (pmd_mac_address(fd, dev, &pmd->eth_addr) < 0) {
> +		rte_free(pmd);

rte_free(data) or goto error_exit; ?


<..>

> +static int
> +set_interface_name(const char *key __rte_unused,
> +		   const char *value,
> +		   void *extra_args)
> +{
> +	char *name = (char *)extra_args;
> +
> +	if (value)
> +		snprintf(name, RTE_ETH_NAME_MAX_LEN-1, "%s", value);

syntax, space around "-"

> +	else
> +		snprintf(name, RTE_ETH_NAME_MAX_LEN-1, "%s%d",

syntax, space around "-"

> +			 DEFAULT_TAP_NAME, (tap_unit-1));

syntax, space around "-"

> +
> +	return 0;
> +}
> +
> +static int
> +set_interface_speed(const char *key __rte_unused,
> +		    const char *value,
> +		    void *extra_args)
> +{
> +	*(int *)extra_args = (value)? atoi(value) : ETH_SPEED_NUM_10G;

syntax, space around "?"

<..>

> +		kvlist = rte_kvargs_parse(params, valid_arguments);
> +		if (kvlist) {
> +			if (rte_kvargs_count(kvlist, ETH_TAP_SPEED_ARG) == 1) {
> +				ret = rte_kvargs_process(kvlist,
> +							 ETH_TAP_SPEED_ARG,
> +							 &set_interface_speed,
> +						         &speed);

whitespace, space and tab mixed

> +				if (ret == -1)
> +					goto leave;
> +			}
> +
> +			if (rte_kvargs_count(kvlist, ETH_TAP_IFACE_ARG) == 1) {
> +				ret = rte_kvargs_process(kvlist,
> +							 ETH_TAP_IFACE_ARG,
> +							 &set_interface_name,
> +						         tap_name);

whitespace, space and tab mixed

<..>

> +static int
> +rte_pmd_tap_remove(const char *name)
> +{
> +	struct rte_eth_dev *eth_dev = NULL;
> +	struct pmd_internals *internals;
> +	int i;
> +
> +	RTE_LOG(INFO, PMD, "Closing TUN/TAP Ethernet device on numa %u\n",
> +		rte_socket_id());
> +
> +	/* find the ethdev entry */
> +	eth_dev = rte_eth_dev_allocated(name);

This may cause a problem. Device created by tap_name, but searching with
name. I suspenct this will always return NULL.

<..>

Thanks,
ferru