[dpdk-dev] [PATCH v3] net/tap: remove Linux version check

[Pascal Mazon]

Ok for me.

Cheers,
Pascal

Acked-by: Pascal Mazon <pascal.mazon at 6wind.com>

On 07/17/2017 11:00 AM, Raslan Darawsheh wrote:
> Remove checks of Linux kernel version
> in order to support kernel with backported features.
>
> the expected behavior with a kernel that doesn't support flower
> and other bits is the following:
>          -flow validate can return successfully
>          -flow create using the same rule fails.
>
> Using the "remote" feature without kernel flower does not fail silently.
> The TAP instance is not initialized if the requested parameters cannot
> be satisfied.
>
> it has been tested on an old kernel without required support:
>
> PMD: Kernel refused TC filter rule creation (2): No such file or directory
> PMD: tap0 failed to create implicit rules.
> PMD: Can't set up remote feature: No such file of directory(2)
> PMD: TAP Unable to initialize net_tap0
>
> Signed-off-by: Raslan Darawsheh <rasland at mellanox.com>
> ---
>   drivers/net/tap/rte_eth_tap.c | 34 +---------------------------------
>   drivers/net/tap/rte_eth_tap.h |  2 --
>   drivers/net/tap/tap_flow.c    | 19 +++++--------------
>   3 files changed, 6 insertions(+), 49 deletions(-)
>
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index a4e5d11..c2b1d8a 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -1166,23 +1166,6 @@ static const struct eth_dev_ops ops = {
>   	.filter_ctrl            = tap_dev_filter_ctrl,
>   };
>   
> -static int
> -tap_kernel_support(struct pmd_internals *pmd)
> -{
> -	struct utsname utsname;
> -	int ver[3];
> -
> -	if (uname(&utsname) == -1 ||
> -	    sscanf(utsname.release, "%d.%d.%d",
> -		   &ver[0], &ver[1], &ver[2]) != 3)
> -		return 0;
> -	if (KERNEL_VERSION(ver[0], ver[1], ver[2]) >= FLOWER_KERNEL_VERSION)
> -		pmd->flower_support = 1;
> -	if (KERNEL_VERSION(ver[0], ver[1], ver[2]) >=
> -	    FLOWER_VLAN_KERNEL_VERSION)
> -		pmd->flower_vlan_support = 1;
> -	return 1;
> -}
>   
>   static int
>   eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
> @@ -1271,20 +1254,6 @@ eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
>   	if (tap_ioctl(pmd, SIOCSIFHWADDR, &ifr, 0, LOCAL_ONLY) < 0)
>   		goto error_exit;
>   
> -	tap_kernel_support(pmd);
> -	if (!pmd->flower_support) {
> -		if (remote_iface[0]) {
> -			RTE_LOG(ERR, PMD,
> -				"%s: kernel does not support TC rules, required for remote feature.",
> -				pmd->name);
> -			goto error_exit;
> -		} else {
> -			RTE_LOG(INFO, PMD,
> -				"%s: kernel too old for Flow API support.\n",
> -				pmd->name);
> -			return 0;
> -		}
> -	}
>   
>   	/*
>   	 * Set up everything related to rte_flow:
> @@ -1378,7 +1347,6 @@ eth_dev_tap_create(struct rte_vdev_device *vdev, char *tap_name,
>   		RTE_LOG(ERR, PMD, "Remote feature requires flow support.\n");
>   		goto error_exit;
>   	}
> -	pmd->flower_support = 0;
>   	return 0;
>   
>   error_remote:
> @@ -1543,7 +1511,7 @@ rte_pmd_tap_remove(struct rte_vdev_device *dev)
>   		return 0;
>   
>   	internals = eth_dev->data->dev_private;
> -	if (internals->flower_support && internals->nlsk_fd) {
> +	if (internals->nlsk_fd) {
>   		tap_flow_flush(eth_dev, NULL);
>   		tap_flow_implicit_flush(internals, NULL);
>   		nl_final(internals->nlsk_fd);
> diff --git a/drivers/net/tap/rte_eth_tap.h b/drivers/net/tap/rte_eth_tap.h
> index 33e1a52..928a045 100644
> --- a/drivers/net/tap/rte_eth_tap.h
> +++ b/drivers/net/tap/rte_eth_tap.h
> @@ -90,8 +90,6 @@ struct pmd_internals {
>   	int ioctl_sock;                   /* socket for ioctl calls */
>   	int nlsk_fd;                      /* Netlink socket fd */
>   	int flow_isolate;                 /* 1 if flow isolation is enabled */
> -	int flower_support;               /* 1 if kernel supports, else 0 */
> -	int flower_vlan_support;          /* 1 if kernel supports, else 0 */
>   	LIST_HEAD(tap_flows, rte_flow) flows;        /* rte_flow rules */
>   	/* implicit rte_flow rules set when a remote device is active */
>   	LIST_HEAD(tap_implicit_flows, rte_flow) implicit_flows;
> diff --git a/drivers/net/tap/tap_flow.c b/drivers/net/tap/tap_flow.c
> index 18425eb..77d4fc4 100644
> --- a/drivers/net/tap/tap_flow.c
> +++ b/drivers/net/tap/tap_flow.c
> @@ -1034,16 +1034,13 @@ priv_flow_process(struct pmd_internals *pmd,
>   		if (err)
>   			goto exit_item_not_supported;
>   		if (flow && cur_item->convert) {
> -			if (!pmd->flower_vlan_support &&
> -			    cur_item->convert == tap_flow_create_vlan)
> -				goto exit_item_not_supported;
>   			err = cur_item->convert(items, &data);
>   			if (err)
>   				goto exit_item_not_supported;
>   		}
>   	}
>   	if (flow) {
> -		if (pmd->flower_vlan_support && data.vlan) {
> +		if (data.vlan) {
>   			nlattr_add16(&flow->msg.nh, TCA_FLOWER_KEY_ETH_TYPE,
>   				     htons(ETH_P_8021Q));
>   			nlattr_add16(&flow->msg.nh,
> @@ -1231,7 +1228,8 @@ tap_flow_create(struct rte_eth_dev *dev,
>   			"Kernel refused TC filter rule creation (%d): %s\n",
>   			errno, strerror(errno));
>   		rte_flow_error_set(error, EEXIST, RTE_FLOW_ERROR_TYPE_HANDLE,
> -				   NULL, "overlapping rules");
> +				   NULL,
> +				   "overlapping rules or Kernel too old for flower support");
>   		goto fail;
>   	}
>   	LIST_INSERT_HEAD(&pmd->flows, flow, next);
> @@ -1276,7 +1274,8 @@ tap_flow_create(struct rte_eth_dev *dev,
>   				errno, strerror(errno));
>   			rte_flow_error_set(
>   				error, ENOMEM, RTE_FLOW_ERROR_TYPE_HANDLE,
> -				NULL, "overlapping rules");
> +				NULL,
> +				"overlapping rules or Kernel too old for flower support");
>   			goto fail;
>   		}
>   		flow->remote_flow = remote_flow;
> @@ -1393,10 +1392,6 @@ tap_flow_isolate(struct rte_eth_dev *dev,
>   {
>   	struct pmd_internals *pmd = dev->data->dev_private;
>   
> -	if (!pmd->flower_support)
> -		return -rte_flow_error_set(
> -			error, ENOTSUP, RTE_FLOW_ERROR_TYPE_UNSPECIFIED, NULL,
> -			"rte_flow isolate requires TC flower kernel support");
>   	if (set)
>   		pmd->flow_isolate = 1;
>   	else
> @@ -1642,10 +1637,6 @@ tap_dev_filter_ctrl(struct rte_eth_dev *dev,
>   		    enum rte_filter_op filter_op,
>   		    void *arg)
>   {
> -	struct pmd_internals *pmd = dev->data->dev_private;
> -
> -	if (!pmd->flower_support)
> -		return -ENOTSUP;
>   	switch (filter_type) {
>   	case RTE_ETH_FILTER_GENERIC:
>   		if (filter_op != RTE_ETH_FILTER_GET)