diff mbox series

[RFC,v2,2/4] virtio-net: support receive timestamp

Message ID 20210208185558.995292-3-willemdebruijn.kernel@gmail.com
State New
Headers show
Series virtio-net: add tx-hash, rx-tstamp, tx-tstamp and tx-time | expand

Commit Message

Willem de Bruijn Feb. 8, 2021, 6:55 p.m. UTC
From: Willem de Bruijn <willemb@google.com>

Add optional PTP hardware rx timestamp offload for virtio-net.

Accurate RTT measurement requires timestamps close to the wire.
Introduce virtio feature VIRTIO_NET_F_RX_TSTAMP. If negotiated, the
virtio-net header is expanded with room for a timestamp.

A device may pass receive timestamps for all or some packets. Flag
VIRTIO_NET_HDR_F_TSTAMP signals whether a timestamp is recorded.

A driver that supports hardware timestamping must also support
ioctl SIOCSHWTSTAMP. Implement that, as well as information getters
ioctl SIOCGHWTSTAMP and ethtool get_ts_info (`ethtool -T $DEV`).

The timestamp straddles (virtual) hardware domains. Like PTP, use
international atomic time (CLOCK_TAI) as global clock base. The driver
must sync with the device, e.g., through kvm-clock.

Tested:
  guest: ./timestamping eth0 \
          SOF_TIMESTAMPING_RAW_HARDWARE \
          SOF_TIMESTAMPING_RX_HARDWARE
  host: nc -4 -u 192.168.1.1 319

Changes RFC -> RFCv2
  - rename virtio_net_hdr_v12 to virtio_net_hdr_hash_ts
  - add ethtool .get_ts_info to query capabilities
  - add ioctl SIOC[GS]HWTSTAMP to configure feature
  - add vi->enable_rx_tstamp to store configuration
  - convert virtioXX_to_cpu to leXX_to_cpu
  - convert reserved to __u32

Signed-off-by: Willem de Bruijn <willemb@google.com>
---
 drivers/net/virtio_net.c        | 113 +++++++++++++++++++++++++++++++-
 include/uapi/linux/virtio_net.h |  13 ++++
 2 files changed, 124 insertions(+), 2 deletions(-)

Comments

Jason Wang Feb. 9, 2021, 4:13 a.m. UTC | #1
On 2021/2/9 上午2:55, Willem de Bruijn wrote:
> From: Willem de Bruijn <willemb@google.com>

>

> Add optional PTP hardware rx timestamp offload for virtio-net.

>

> Accurate RTT measurement requires timestamps close to the wire.

> Introduce virtio feature VIRTIO_NET_F_RX_TSTAMP. If negotiated, the

> virtio-net header is expanded with room for a timestamp.

>

> A device may pass receive timestamps for all or some packets. Flag

> VIRTIO_NET_HDR_F_TSTAMP signals whether a timestamp is recorded.

>

> A driver that supports hardware timestamping must also support

> ioctl SIOCSHWTSTAMP. Implement that, as well as information getters

> ioctl SIOCGHWTSTAMP and ethtool get_ts_info (`ethtool -T $DEV`).

>

> The timestamp straddles (virtual) hardware domains. Like PTP, use

> international atomic time (CLOCK_TAI) as global clock base. The driver

> must sync with the device, e.g., through kvm-clock.

>

> Tested:

>    guest: ./timestamping eth0 \

>            SOF_TIMESTAMPING_RAW_HARDWARE \

>            SOF_TIMESTAMPING_RX_HARDWARE

>    host: nc -4 -u 192.168.1.1 319

>

> Changes RFC -> RFCv2

>    - rename virtio_net_hdr_v12 to virtio_net_hdr_hash_ts

>    - add ethtool .get_ts_info to query capabilities

>    - add ioctl SIOC[GS]HWTSTAMP to configure feature

>    - add vi->enable_rx_tstamp to store configuration

>    - convert virtioXX_to_cpu to leXX_to_cpu

>    - convert reserved to __u32

>

> Signed-off-by: Willem de Bruijn <willemb@google.com>

> ---

>   drivers/net/virtio_net.c        | 113 +++++++++++++++++++++++++++++++-

>   include/uapi/linux/virtio_net.h |  13 ++++

>   2 files changed, 124 insertions(+), 2 deletions(-)

>

> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c

> index 7f822b2a5205..ac44c5efa0bc 100644

> --- a/drivers/net/virtio_net.c

> +++ b/drivers/net/virtio_net.c

> @@ -204,6 +204,12 @@ struct virtnet_info {

>   	/* Driver will pass tx path info to the device */

>   	bool has_tx_hash;

>   

> +	/* Device can pass CLOCK_TAI receive time to the driver */

> +	bool has_rx_tstamp;

> +

> +	/* Device will pass rx timestamp. Requires has_rx_tstamp */

> +	bool enable_rx_tstamp;

> +

>   	/* Has control virtqueue */

>   	bool has_cvq;

>   

> @@ -292,6 +298,13 @@ static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)

>   	return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;

>   }

>   

> +static inline struct virtio_net_hdr_hash_ts *skb_vnet_hdr_ht(struct sk_buff *skb)

> +{

> +	BUILD_BUG_ON(sizeof(struct virtio_net_hdr_hash_ts) > sizeof(skb->cb));

> +

> +	return (void *)skb->cb;

> +}

> +

>   /*

>    * private is used to chain pages for big packets, put the whole

>    * most recent used list in the beginning for reuse

> @@ -1030,6 +1043,19 @@ static struct sk_buff *receive_mergeable(struct net_device *dev,

>   	return NULL;

>   }

>   

> +static inline void virtnet_record_rx_tstamp(const struct virtnet_info *vi,

> +					    struct sk_buff *skb)

> +{

> +	const struct virtio_net_hdr_hash_ts *h = skb_vnet_hdr_ht(skb);

> +

> +	if (h->hdr.flags & VIRTIO_NET_HDR_F_TSTAMP &&

> +	    vi->enable_rx_tstamp) {

> +		u64 ts = le64_to_cpu(h->tstamp);

> +

> +		skb_hwtstamps(skb)->hwtstamp = ns_to_ktime(ts);

> +	}

> +}

> +

>   static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,

>   			void *buf, unsigned int len, void **ctx,

>   			unsigned int *xdp_xmit,

> @@ -1076,6 +1102,7 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,

>   		goto frame_err;

>   	}

>   

> +	virtnet_record_rx_tstamp(vi, skb);

>   	skb_record_rx_queue(skb, vq2rxq(rq->vq));

>   	skb->protocol = eth_type_trans(skb, dev);

>   	pr_debug("Receiving skb proto 0x%04x len %i type %i\n",

> @@ -2263,6 +2290,28 @@ static int virtnet_get_coalesce(struct net_device *dev,

>   	return 0;

>   }

>   

> +static int virtnet_get_ts_info(struct net_device *dev,

> +			       struct ethtool_ts_info *info)

> +{

> +	struct virtnet_info *vi = netdev_priv(dev);

> +

> +	/* setup default software timestamp */

> +	ethtool_op_get_ts_info(dev, info);

> +

> +	/* return rx capabilities (which may differ from current enable) */

> +	if (vi->has_rx_tstamp) {

> +		info->so_timestamping |= SOF_TIMESTAMPING_RX_HARDWARE |

> +					 SOF_TIMESTAMPING_RAW_HARDWARE;

> +		info->rx_filters = HWTSTAMP_FILTER_ALL;

> +	} else {

> +		info->rx_filters = HWTSTAMP_FILTER_NONE;

> +	}

> +

> +	info->tx_types = HWTSTAMP_TX_OFF;

> +

> +	return 0;

> +}

> +

>   static void virtnet_init_settings(struct net_device *dev)

>   {

>   	struct virtnet_info *vi = netdev_priv(dev);

> @@ -2300,7 +2349,7 @@ static const struct ethtool_ops virtnet_ethtool_ops = {

>   	.get_ethtool_stats = virtnet_get_ethtool_stats,

>   	.set_channels = virtnet_set_channels,

>   	.get_channels = virtnet_get_channels,

> -	.get_ts_info = ethtool_op_get_ts_info,

> +	.get_ts_info = virtnet_get_ts_info,

>   	.get_link_ksettings = virtnet_get_link_ksettings,

>   	.set_link_ksettings = virtnet_set_link_ksettings,

>   	.set_coalesce = virtnet_set_coalesce,

> @@ -2558,6 +2607,60 @@ static int virtnet_set_features(struct net_device *dev,

>   	return 0;

>   }

>   

> +static int virtnet_ioctl_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)

> +{

> +	struct virtnet_info *vi = netdev_priv(dev);

> +	struct hwtstamp_config tsconf;

> +

> +	if (copy_from_user(&tsconf, ifr->ifr_data, sizeof(tsconf)))

> +		return -EFAULT;

> +	if (tsconf.flags)

> +		return -EINVAL;

> +	if (tsconf.tx_type != HWTSTAMP_TX_OFF)

> +		return -ERANGE;

> +	if (tsconf.rx_filter != HWTSTAMP_FILTER_NONE &&

> +	    tsconf.rx_filter != HWTSTAMP_FILTER_ALL)

> +		tsconf.rx_filter = HWTSTAMP_FILTER_ALL;

> +

> +	if (!vi->has_rx_tstamp)

> +		tsconf.rx_filter = HWTSTAMP_FILTER_NONE;

> +	else

> +		vi->enable_rx_tstamp = tsconf.rx_filter == HWTSTAMP_FILTER_ALL;

> +

> +	if (copy_to_user(ifr->ifr_data, &tsconf, sizeof(tsconf)))

> +		return -EFAULT;

> +

> +	return 0;

> +}

> +

> +static int virtnet_ioctl_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)

> +{

> +	struct virtnet_info *vi = netdev_priv(dev);

> +	struct hwtstamp_config tsconf;

> +

> +	tsconf.flags = 0;

> +	tsconf.rx_filter = vi->enable_rx_tstamp ? HWTSTAMP_FILTER_ALL :

> +						  HWTSTAMP_FILTER_NONE;

> +	tsconf.tx_type = HWTSTAMP_TX_OFF;

> +

> +	if (copy_to_user(ifr->ifr_data, &tsconf, sizeof(tsconf)))

> +		return -EFAULT;

> +

> +	return 0;

> +}

> +

> +static int virtnet_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)

> +{

> +	switch (cmd) {

> +	case SIOCSHWTSTAMP:

> +		return virtnet_ioctl_set_hwtstamp(dev, ifr);

> +

> +	case SIOCGHWTSTAMP:

> +		return virtnet_ioctl_get_hwtstamp(dev, ifr);

> +	}

> +	return -EOPNOTSUPP;

> +}

> +

>   static const struct net_device_ops virtnet_netdev = {

>   	.ndo_open            = virtnet_open,

>   	.ndo_stop   	     = virtnet_close,

> @@ -2573,6 +2676,7 @@ static const struct net_device_ops virtnet_netdev = {

>   	.ndo_features_check	= passthru_features_check,

>   	.ndo_get_phys_port_name	= virtnet_get_phys_port_name,

>   	.ndo_set_features	= virtnet_set_features,

> +	.ndo_do_ioctl		= virtnet_ioctl,

>   };

>   

>   static void virtnet_config_changed_work(struct work_struct *work)

> @@ -3069,6 +3173,11 @@ static int virtnet_probe(struct virtio_device *vdev)

>   		vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);

>   	}

>   

> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_RX_TSTAMP)) {

> +		vi->has_rx_tstamp = true;

> +		vi->hdr_len = sizeof(struct virtio_net_hdr_hash_ts);



Does this mean even if the device doesn't pass timestamp, the header 
still contains the timestamp fields.


> +	}

> +

>   	if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||

>   	    virtio_has_feature(vdev, VIRTIO_F_VERSION_1))

>   		vi->any_header_sg = true;

> @@ -3260,7 +3369,7 @@ static struct virtio_device_id id_table[] = {

>   	VIRTIO_NET_F_CTRL_MAC_ADDR, \

>   	VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \

>   	VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \

> -	VIRTIO_NET_F_TX_HASH

> +	VIRTIO_NET_F_TX_HASH, VIRTIO_NET_F_RX_TSTAMP

>   

>   static unsigned int features[] = {

>   	VIRTNET_FEATURES,

> diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h

> index 273d43c35f59..a5c84410cf92 100644

> --- a/include/uapi/linux/virtio_net.h

> +++ b/include/uapi/linux/virtio_net.h

> @@ -57,6 +57,7 @@

>   					 * Steering */

>   #define VIRTIO_NET_F_CTRL_MAC_ADDR 23	/* Set MAC address */

>   

> +#define VIRTIO_NET_F_RX_TSTAMP	  55	/* Device sends TAI receive time */

>   #define VIRTIO_NET_F_TX_HASH	  56	/* Driver sends hash report */

>   #define VIRTIO_NET_F_HASH_REPORT  57	/* Supports hash report */

>   #define VIRTIO_NET_F_RSS	  60	/* Supports RSS RX steering */

> @@ -126,6 +127,7 @@ struct virtio_net_hdr_v1 {

>   #define VIRTIO_NET_HDR_F_NEEDS_CSUM	1	/* Use csum_start, csum_offset */

>   #define VIRTIO_NET_HDR_F_DATA_VALID	2	/* Csum is valid */

>   #define VIRTIO_NET_HDR_F_RSC_INFO	4	/* rsc info in csum_ fields */

> +#define VIRTIO_NET_HDR_F_TSTAMP		8	/* timestamp is recorded */

>   	__u8 flags;

>   #define VIRTIO_NET_HDR_GSO_NONE		0	/* Not a GSO frame */

>   #define VIRTIO_NET_HDR_GSO_TCPV4	1	/* GSO frame, IPv4 TCP (TSO) */

> @@ -181,6 +183,17 @@ struct virtio_net_hdr_v1_hash {

>   	};

>   };

>   

> +struct virtio_net_hdr_hash_ts {

> +	struct virtio_net_hdr_v1 hdr;

> +	struct {

> +		__le32 value;

> +		__le16 report;

> +		__le16 flow_state;

> +	} hash;



Any reason for not embedding structure virtio_net_hdr_v1_hash?

Thanks


> +	__u32 reserved;

> +	__le64 tstamp;

> +};

> +

>   #ifndef VIRTIO_NET_NO_LEGACY

>   /* This header comes first in the scatter-gather list.

>    * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
Willem de Bruijn Feb. 9, 2021, 1:53 p.m. UTC | #2
On Mon, Feb 8, 2021 at 11:13 PM Jason Wang <jasowang@redhat.com> wrote:
>

>

> On 2021/2/9 上午2:55, Willem de Bruijn wrote:

> > From: Willem de Bruijn <willemb@google.com>

> >

> > Add optional PTP hardware rx timestamp offload for virtio-net.

> >

> > Accurate RTT measurement requires timestamps close to the wire.

> > Introduce virtio feature VIRTIO_NET_F_RX_TSTAMP. If negotiated, the

> > virtio-net header is expanded with room for a timestamp.

> >

> > A device may pass receive timestamps for all or some packets. Flag

> > VIRTIO_NET_HDR_F_TSTAMP signals whether a timestamp is recorded.

> >

> > A driver that supports hardware timestamping must also support

> > ioctl SIOCSHWTSTAMP. Implement that, as well as information getters

> > ioctl SIOCGHWTSTAMP and ethtool get_ts_info (`ethtool -T $DEV`).

> >

> > The timestamp straddles (virtual) hardware domains. Like PTP, use

> > international atomic time (CLOCK_TAI) as global clock base. The driver

> > must sync with the device, e.g., through kvm-clock.

> >

> > Tested:

> >    guest: ./timestamping eth0 \

> >            SOF_TIMESTAMPING_RAW_HARDWARE \

> >            SOF_TIMESTAMPING_RX_HARDWARE

> >    host: nc -4 -u 192.168.1.1 319

> >

> > Changes RFC -> RFCv2

> >    - rename virtio_net_hdr_v12 to virtio_net_hdr_hash_ts

> >    - add ethtool .get_ts_info to query capabilities

> >    - add ioctl SIOC[GS]HWTSTAMP to configure feature

> >    - add vi->enable_rx_tstamp to store configuration

> >    - convert virtioXX_to_cpu to leXX_to_cpu

> >    - convert reserved to __u32

> >

> > Signed-off-by: Willem de Bruijn <willemb@google.com>


> >   static const struct net_device_ops virtnet_netdev = {

> >       .ndo_open            = virtnet_open,

> >       .ndo_stop            = virtnet_close,

> > @@ -2573,6 +2676,7 @@ static const struct net_device_ops virtnet_netdev = {

> >       .ndo_features_check     = passthru_features_check,

> >       .ndo_get_phys_port_name = virtnet_get_phys_port_name,

> >       .ndo_set_features       = virtnet_set_features,

> > +     .ndo_do_ioctl           = virtnet_ioctl,

> >   };

> >

> >   static void virtnet_config_changed_work(struct work_struct *work)

> > @@ -3069,6 +3173,11 @@ static int virtnet_probe(struct virtio_device *vdev)

> >               vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);

> >       }

> >

> > +     if (virtio_has_feature(vdev, VIRTIO_NET_F_RX_TSTAMP)) {

> > +             vi->has_rx_tstamp = true;

> > +             vi->hdr_len = sizeof(struct virtio_net_hdr_hash_ts);

>

>

> Does this mean even if the device doesn't pass timestamp, the header

> still contains the timestamp fields.


Yes. As implemented, the size of the header is constant across
packets. If both sides negotiate the feature, then all headers reserve
space, whether or not the specific packet has a timestamp.

So far headers are fixed size. I suppose we could investigate variable
size headers. This goes back to our discussion in the previous
patchset, that we can always add a packed-header feature later, if the
number of optional features reaches a size that makes the complexity
worthwhile.

> > +     }

> > +

> >       if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||

> >           virtio_has_feature(vdev, VIRTIO_F_VERSION_1))

> >               vi->any_header_sg = true;

> > @@ -3260,7 +3369,7 @@ static struct virtio_device_id id_table[] = {

> >       VIRTIO_NET_F_CTRL_MAC_ADDR, \

> >       VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \

> >       VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \

> > -     VIRTIO_NET_F_TX_HASH

> > +     VIRTIO_NET_F_TX_HASH, VIRTIO_NET_F_RX_TSTAMP

> >

> >   static unsigned int features[] = {

> >       VIRTNET_FEATURES,

> > diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h

> > index 273d43c35f59..a5c84410cf92 100644

> > --- a/include/uapi/linux/virtio_net.h

> > +++ b/include/uapi/linux/virtio_net.h

> > @@ -57,6 +57,7 @@

> >                                        * Steering */

> >   #define VIRTIO_NET_F_CTRL_MAC_ADDR 23       /* Set MAC address */

> >

> > +#define VIRTIO_NET_F_RX_TSTAMP         55    /* Device sends TAI receive time */

> >   #define VIRTIO_NET_F_TX_HASH          56    /* Driver sends hash report */

> >   #define VIRTIO_NET_F_HASH_REPORT  57        /* Supports hash report */

> >   #define VIRTIO_NET_F_RSS      60    /* Supports RSS RX steering */

> > @@ -126,6 +127,7 @@ struct virtio_net_hdr_v1 {

> >   #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1       /* Use csum_start, csum_offset */

> >   #define VIRTIO_NET_HDR_F_DATA_VALID 2       /* Csum is valid */

> >   #define VIRTIO_NET_HDR_F_RSC_INFO   4       /* rsc info in csum_ fields */

> > +#define VIRTIO_NET_HDR_F_TSTAMP              8       /* timestamp is recorded */

> >       __u8 flags;

> >   #define VIRTIO_NET_HDR_GSO_NONE             0       /* Not a GSO frame */

> >   #define VIRTIO_NET_HDR_GSO_TCPV4    1       /* GSO frame, IPv4 TCP (TSO) */

> > @@ -181,6 +183,17 @@ struct virtio_net_hdr_v1_hash {

> >       };

> >   };

> >

> > +struct virtio_net_hdr_hash_ts {

> > +     struct virtio_net_hdr_v1 hdr;

> > +     struct {

> > +             __le32 value;

> > +             __le16 report;

> > +             __le16 flow_state;

> > +     } hash;

>

>

> Any reason for not embedding structure virtio_net_hdr_v1_hash?


Just that it becomes an onion of struct inside structs. I can change
if you prefer.

> Thanks


As always, thanks for reviewing, Jason.
Jason Wang Feb. 10, 2021, 4:10 a.m. UTC | #3
On 2021/2/9 下午9:53, Willem de Bruijn wrote:
> On Mon, Feb 8, 2021 at 11:13 PM Jason Wang <jasowang@redhat.com> wrote:

>>

>> On 2021/2/9 上午2:55, Willem de Bruijn wrote:

>>> From: Willem de Bruijn <willemb@google.com>

>>>

>>> Add optional PTP hardware rx timestamp offload for virtio-net.

>>>

>>> Accurate RTT measurement requires timestamps close to the wire.

>>> Introduce virtio feature VIRTIO_NET_F_RX_TSTAMP. If negotiated, the

>>> virtio-net header is expanded with room for a timestamp.

>>>

>>> A device may pass receive timestamps for all or some packets. Flag

>>> VIRTIO_NET_HDR_F_TSTAMP signals whether a timestamp is recorded.

>>>

>>> A driver that supports hardware timestamping must also support

>>> ioctl SIOCSHWTSTAMP. Implement that, as well as information getters

>>> ioctl SIOCGHWTSTAMP and ethtool get_ts_info (`ethtool -T $DEV`).

>>>

>>> The timestamp straddles (virtual) hardware domains. Like PTP, use

>>> international atomic time (CLOCK_TAI) as global clock base. The driver

>>> must sync with the device, e.g., through kvm-clock.

>>>

>>> Tested:

>>>     guest: ./timestamping eth0 \

>>>             SOF_TIMESTAMPING_RAW_HARDWARE \

>>>             SOF_TIMESTAMPING_RX_HARDWARE

>>>     host: nc -4 -u 192.168.1.1 319

>>>

>>> Changes RFC -> RFCv2

>>>     - rename virtio_net_hdr_v12 to virtio_net_hdr_hash_ts

>>>     - add ethtool .get_ts_info to query capabilities

>>>     - add ioctl SIOC[GS]HWTSTAMP to configure feature

>>>     - add vi->enable_rx_tstamp to store configuration

>>>     - convert virtioXX_to_cpu to leXX_to_cpu

>>>     - convert reserved to __u32

>>>

>>> Signed-off-by: Willem de Bruijn <willemb@google.com>

>>>    static const struct net_device_ops virtnet_netdev = {

>>>        .ndo_open            = virtnet_open,

>>>        .ndo_stop            = virtnet_close,

>>> @@ -2573,6 +2676,7 @@ static const struct net_device_ops virtnet_netdev = {

>>>        .ndo_features_check     = passthru_features_check,

>>>        .ndo_get_phys_port_name = virtnet_get_phys_port_name,

>>>        .ndo_set_features       = virtnet_set_features,

>>> +     .ndo_do_ioctl           = virtnet_ioctl,

>>>    };

>>>

>>>    static void virtnet_config_changed_work(struct work_struct *work)

>>> @@ -3069,6 +3173,11 @@ static int virtnet_probe(struct virtio_device *vdev)

>>>                vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);

>>>        }

>>>

>>> +     if (virtio_has_feature(vdev, VIRTIO_NET_F_RX_TSTAMP)) {

>>> +             vi->has_rx_tstamp = true;

>>> +             vi->hdr_len = sizeof(struct virtio_net_hdr_hash_ts);

>>

>> Does this mean even if the device doesn't pass timestamp, the header

>> still contains the timestamp fields.

> Yes. As implemented, the size of the header is constant across

> packets. If both sides negotiate the feature, then all headers reserve

> space, whether or not the specific packet has a timestamp.

>

> So far headers are fixed size. I suppose we could investigate variable

> size headers. This goes back to our discussion in the previous

> patchset, that we can always add a packed-header feature later, if the

> number of optional features reaches a size that makes the complexity

> worthwhile.



Right, so for timstamp it's probably OK but we probably need to do as 
you said here if we want to add more in the header. Let's see how 
Michael think about this.


>

>>> +     }

>>> +

>>>        if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||

>>>            virtio_has_feature(vdev, VIRTIO_F_VERSION_1))

>>>                vi->any_header_sg = true;

>>> @@ -3260,7 +3369,7 @@ static struct virtio_device_id id_table[] = {

>>>        VIRTIO_NET_F_CTRL_MAC_ADDR, \

>>>        VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \

>>>        VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \

>>> -     VIRTIO_NET_F_TX_HASH

>>> +     VIRTIO_NET_F_TX_HASH, VIRTIO_NET_F_RX_TSTAMP

>>>

>>>    static unsigned int features[] = {

>>>        VIRTNET_FEATURES,

>>> diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h

>>> index 273d43c35f59..a5c84410cf92 100644

>>> --- a/include/uapi/linux/virtio_net.h

>>> +++ b/include/uapi/linux/virtio_net.h

>>> @@ -57,6 +57,7 @@

>>>                                         * Steering */

>>>    #define VIRTIO_NET_F_CTRL_MAC_ADDR 23       /* Set MAC address */

>>>

>>> +#define VIRTIO_NET_F_RX_TSTAMP         55    /* Device sends TAI receive time */

>>>    #define VIRTIO_NET_F_TX_HASH          56    /* Driver sends hash report */

>>>    #define VIRTIO_NET_F_HASH_REPORT  57        /* Supports hash report */

>>>    #define VIRTIO_NET_F_RSS      60    /* Supports RSS RX steering */

>>> @@ -126,6 +127,7 @@ struct virtio_net_hdr_v1 {

>>>    #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1       /* Use csum_start, csum_offset */

>>>    #define VIRTIO_NET_HDR_F_DATA_VALID 2       /* Csum is valid */

>>>    #define VIRTIO_NET_HDR_F_RSC_INFO   4       /* rsc info in csum_ fields */

>>> +#define VIRTIO_NET_HDR_F_TSTAMP              8       /* timestamp is recorded */

>>>        __u8 flags;

>>>    #define VIRTIO_NET_HDR_GSO_NONE             0       /* Not a GSO frame */

>>>    #define VIRTIO_NET_HDR_GSO_TCPV4    1       /* GSO frame, IPv4 TCP (TSO) */

>>> @@ -181,6 +183,17 @@ struct virtio_net_hdr_v1_hash {

>>>        };

>>>    };

>>>

>>> +struct virtio_net_hdr_hash_ts {

>>> +     struct virtio_net_hdr_v1 hdr;

>>> +     struct {

>>> +             __le32 value;

>>> +             __le16 report;

>>> +             __le16 flow_state;

>>> +     } hash;

>>

>> Any reason for not embedding structure virtio_net_hdr_v1_hash?

> Just that it becomes an onion of struct inside structs. I can change

> if you prefer.



Yes please (unless Michael has other opinion).


>

>> Thanks

> As always, thanks for reviewing, Jason.

>


You're welcome :)

Thanks
diff mbox series

Patch

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 7f822b2a5205..ac44c5efa0bc 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -204,6 +204,12 @@  struct virtnet_info {
 	/* Driver will pass tx path info to the device */
 	bool has_tx_hash;
 
+	/* Device can pass CLOCK_TAI receive time to the driver */
+	bool has_rx_tstamp;
+
+	/* Device will pass rx timestamp. Requires has_rx_tstamp */
+	bool enable_rx_tstamp;
+
 	/* Has control virtqueue */
 	bool has_cvq;
 
@@ -292,6 +298,13 @@  static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
 	return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
 }
 
+static inline struct virtio_net_hdr_hash_ts *skb_vnet_hdr_ht(struct sk_buff *skb)
+{
+	BUILD_BUG_ON(sizeof(struct virtio_net_hdr_hash_ts) > sizeof(skb->cb));
+
+	return (void *)skb->cb;
+}
+
 /*
  * private is used to chain pages for big packets, put the whole
  * most recent used list in the beginning for reuse
@@ -1030,6 +1043,19 @@  static struct sk_buff *receive_mergeable(struct net_device *dev,
 	return NULL;
 }
 
+static inline void virtnet_record_rx_tstamp(const struct virtnet_info *vi,
+					    struct sk_buff *skb)
+{
+	const struct virtio_net_hdr_hash_ts *h = skb_vnet_hdr_ht(skb);
+
+	if (h->hdr.flags & VIRTIO_NET_HDR_F_TSTAMP &&
+	    vi->enable_rx_tstamp) {
+		u64 ts = le64_to_cpu(h->tstamp);
+
+		skb_hwtstamps(skb)->hwtstamp = ns_to_ktime(ts);
+	}
+}
+
 static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
 			void *buf, unsigned int len, void **ctx,
 			unsigned int *xdp_xmit,
@@ -1076,6 +1102,7 @@  static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
 		goto frame_err;
 	}
 
+	virtnet_record_rx_tstamp(vi, skb);
 	skb_record_rx_queue(skb, vq2rxq(rq->vq));
 	skb->protocol = eth_type_trans(skb, dev);
 	pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
@@ -2263,6 +2290,28 @@  static int virtnet_get_coalesce(struct net_device *dev,
 	return 0;
 }
 
+static int virtnet_get_ts_info(struct net_device *dev,
+			       struct ethtool_ts_info *info)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+
+	/* setup default software timestamp */
+	ethtool_op_get_ts_info(dev, info);
+
+	/* return rx capabilities (which may differ from current enable) */
+	if (vi->has_rx_tstamp) {
+		info->so_timestamping |= SOF_TIMESTAMPING_RX_HARDWARE |
+					 SOF_TIMESTAMPING_RAW_HARDWARE;
+		info->rx_filters = HWTSTAMP_FILTER_ALL;
+	} else {
+		info->rx_filters = HWTSTAMP_FILTER_NONE;
+	}
+
+	info->tx_types = HWTSTAMP_TX_OFF;
+
+	return 0;
+}
+
 static void virtnet_init_settings(struct net_device *dev)
 {
 	struct virtnet_info *vi = netdev_priv(dev);
@@ -2300,7 +2349,7 @@  static const struct ethtool_ops virtnet_ethtool_ops = {
 	.get_ethtool_stats = virtnet_get_ethtool_stats,
 	.set_channels = virtnet_set_channels,
 	.get_channels = virtnet_get_channels,
-	.get_ts_info = ethtool_op_get_ts_info,
+	.get_ts_info = virtnet_get_ts_info,
 	.get_link_ksettings = virtnet_get_link_ksettings,
 	.set_link_ksettings = virtnet_set_link_ksettings,
 	.set_coalesce = virtnet_set_coalesce,
@@ -2558,6 +2607,60 @@  static int virtnet_set_features(struct net_device *dev,
 	return 0;
 }
 
+static int virtnet_ioctl_set_hwtstamp(struct net_device *dev, struct ifreq *ifr)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct hwtstamp_config tsconf;
+
+	if (copy_from_user(&tsconf, ifr->ifr_data, sizeof(tsconf)))
+		return -EFAULT;
+	if (tsconf.flags)
+		return -EINVAL;
+	if (tsconf.tx_type != HWTSTAMP_TX_OFF)
+		return -ERANGE;
+	if (tsconf.rx_filter != HWTSTAMP_FILTER_NONE &&
+	    tsconf.rx_filter != HWTSTAMP_FILTER_ALL)
+		tsconf.rx_filter = HWTSTAMP_FILTER_ALL;
+
+	if (!vi->has_rx_tstamp)
+		tsconf.rx_filter = HWTSTAMP_FILTER_NONE;
+	else
+		vi->enable_rx_tstamp = tsconf.rx_filter == HWTSTAMP_FILTER_ALL;
+
+	if (copy_to_user(ifr->ifr_data, &tsconf, sizeof(tsconf)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int virtnet_ioctl_get_hwtstamp(struct net_device *dev, struct ifreq *ifr)
+{
+	struct virtnet_info *vi = netdev_priv(dev);
+	struct hwtstamp_config tsconf;
+
+	tsconf.flags = 0;
+	tsconf.rx_filter = vi->enable_rx_tstamp ? HWTSTAMP_FILTER_ALL :
+						  HWTSTAMP_FILTER_NONE;
+	tsconf.tx_type = HWTSTAMP_TX_OFF;
+
+	if (copy_to_user(ifr->ifr_data, &tsconf, sizeof(tsconf)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int virtnet_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	switch (cmd) {
+	case SIOCSHWTSTAMP:
+		return virtnet_ioctl_set_hwtstamp(dev, ifr);
+
+	case SIOCGHWTSTAMP:
+		return virtnet_ioctl_get_hwtstamp(dev, ifr);
+	}
+	return -EOPNOTSUPP;
+}
+
 static const struct net_device_ops virtnet_netdev = {
 	.ndo_open            = virtnet_open,
 	.ndo_stop   	     = virtnet_close,
@@ -2573,6 +2676,7 @@  static const struct net_device_ops virtnet_netdev = {
 	.ndo_features_check	= passthru_features_check,
 	.ndo_get_phys_port_name	= virtnet_get_phys_port_name,
 	.ndo_set_features	= virtnet_set_features,
+	.ndo_do_ioctl		= virtnet_ioctl,
 };
 
 static void virtnet_config_changed_work(struct work_struct *work)
@@ -3069,6 +3173,11 @@  static int virtnet_probe(struct virtio_device *vdev)
 		vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
 	}
 
+	if (virtio_has_feature(vdev, VIRTIO_NET_F_RX_TSTAMP)) {
+		vi->has_rx_tstamp = true;
+		vi->hdr_len = sizeof(struct virtio_net_hdr_hash_ts);
+	}
+
 	if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
 	    virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
 		vi->any_header_sg = true;
@@ -3260,7 +3369,7 @@  static struct virtio_device_id id_table[] = {
 	VIRTIO_NET_F_CTRL_MAC_ADDR, \
 	VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
 	VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
-	VIRTIO_NET_F_TX_HASH
+	VIRTIO_NET_F_TX_HASH, VIRTIO_NET_F_RX_TSTAMP
 
 static unsigned int features[] = {
 	VIRTNET_FEATURES,
diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
index 273d43c35f59..a5c84410cf92 100644
--- a/include/uapi/linux/virtio_net.h
+++ b/include/uapi/linux/virtio_net.h
@@ -57,6 +57,7 @@ 
 					 * Steering */
 #define VIRTIO_NET_F_CTRL_MAC_ADDR 23	/* Set MAC address */
 
+#define VIRTIO_NET_F_RX_TSTAMP	  55	/* Device sends TAI receive time */
 #define VIRTIO_NET_F_TX_HASH	  56	/* Driver sends hash report */
 #define VIRTIO_NET_F_HASH_REPORT  57	/* Supports hash report */
 #define VIRTIO_NET_F_RSS	  60	/* Supports RSS RX steering */
@@ -126,6 +127,7 @@  struct virtio_net_hdr_v1 {
 #define VIRTIO_NET_HDR_F_NEEDS_CSUM	1	/* Use csum_start, csum_offset */
 #define VIRTIO_NET_HDR_F_DATA_VALID	2	/* Csum is valid */
 #define VIRTIO_NET_HDR_F_RSC_INFO	4	/* rsc info in csum_ fields */
+#define VIRTIO_NET_HDR_F_TSTAMP		8	/* timestamp is recorded */
 	__u8 flags;
 #define VIRTIO_NET_HDR_GSO_NONE		0	/* Not a GSO frame */
 #define VIRTIO_NET_HDR_GSO_TCPV4	1	/* GSO frame, IPv4 TCP (TSO) */
@@ -181,6 +183,17 @@  struct virtio_net_hdr_v1_hash {
 	};
 };
 
+struct virtio_net_hdr_hash_ts {
+	struct virtio_net_hdr_v1 hdr;
+	struct {
+		__le32 value;
+		__le16 report;
+		__le16 flow_state;
+	} hash;
+	__u32 reserved;
+	__le64 tstamp;
+};
+
 #ifndef VIRTIO_NET_NO_LEGACY
 /* This header comes first in the scatter-gather list.
  * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must