On Mon, Feb 01, 2021 at 08:05:01AM -0600, George McCollister wrote:
> Add support for offloading of HSR/PRP (IEC 62439-3) tag insertion
> tag removal, duplicate generation and forwarding.
>
> Use a new netdev_priv_flag IFF_HSR to indicate that a device is an HSR
> device so DSA can tell them apart from other devices in
> dsa_slave_changeupper.
My opinion can easily be overridden by somebody with more experience,
but for the purposes of determining whether a net_device is DSA or not,
DSA did not use a priv_flags bit, but simply exported dsa_slave_dev_check
which looks at its netdev_ops.
I am not sure what is the history of the IFF_EBRIDGE/BONDING/... bits,
but it seems a bit wasteful to me to consume the last bit of priv_flags
on something that can be derived from other sources.
I am basing this comment on the fact that your patch series does not
make use of the IFF_SLAVE bit and of netif_is_hsr_slave, and therefore
that you should probably not add a function that is not used, or the
mechanism for it.
>
> For HSR, insertion involves the switch adding a 6 byte HSR header after
> the 14 byte Ethernet header. For PRP it adds a 6 byte trailer.
>
> Tag removal involves automatically stripping the HSR/PRP header/trailer
> in the switch. This is possible when the switch also preforms auto
~~~~~~~~
performs
> deduplication using the HSR/PRP header/trailer (making it no longer
> required).
>
> Forwarding involves automatically forwarding between redundant ports in
> an HSR. This is crucial because delay is accumulated as a frame passes
> through each node in the ring.
>
> Duplication involves the switch automatically sending a single frame
> from the CPU port to both redundant ports. This is required because the
> inserted HSR/PRP header/trailer must contain the same sequence number
> on the frames sent out both redundant ports.
>
> Signed-off-by: George McCollister <george.mccollis...@gmail.com>
> ---
> Documentation/networking/netdev-features.rst | 20 ++++++++++++++++++++
> include/linux/if_hsr.h | 22 ++++++++++++++++++++++
> include/linux/netdev_features.h | 9 +++++++++
> include/linux/netdevice.h | 13 +++++++++++++
> net/ethtool/common.c | 4 ++++
> net/hsr/hsr_device.c | 12 +++---------
> net/hsr/hsr_forward.c | 27 ++++++++++++++++++++++++---
> net/hsr/hsr_forward.h | 1 +
> net/hsr/hsr_main.c | 14 ++++++++++++++
> net/hsr/hsr_main.h | 8 +-------
> net/hsr/hsr_slave.c | 13 +++++++++----
> 11 files changed, 120 insertions(+), 23 deletions(-)
> create mode 100644 include/linux/if_hsr.h
>
> diff --git a/Documentation/networking/netdev-features.rst
> b/Documentation/networking/netdev-features.rst
> index a2d7d7160e39..4eab45405031 100644
> --- a/Documentation/networking/netdev-features.rst
> +++ b/Documentation/networking/netdev-features.rst
> @@ -182,3 +182,23 @@ stricter than Hardware LRO. A packet stream merged by
> Hardware GRO must
> be re-segmentable by GSO or TSO back to the exact original packet stream.
> Hardware GRO is dependent on RXCSUM since every packet successfully merged
> by hardware must also have the checksum verified by hardware.
> +
> +* hsr-tag-ins-offload
> +
> +This should be set for devices which insert an HSR (highspeed ring) tag
~~~~~~~~~~~~~~
The one thing I know about HSR is that it stands for High-availability
Seamless Redundancy, not High Speed Ring.
Also, it would be good to mention that these features apply to PRP too.
> +automatically when in HSR mode.
> +
> +* hsr-tag-rm-offload
> +
> +This should be set for devices which remove HSR (highspeed ring) tags
> +automatically when in HSR mode.
> +
> +* hsr-fwd-offload
> +
> +This should be set for devices which forward HSR (highspeed ring) frames from
> +one port to another in hardware.
> +
> +* hsr-dup-offload
> +
> +This should be set for devices which duplicate outgoing HSR (highspeed ring)
> +frames in hardware.
I don't have a strong opinion on creating ethtool features that are so
fine-grained, but do we really expect to see a net_device capable of
hsr-tag-rm-offload but not hsr-tag-ins-offload, or hsr-dup-offload but
not hsr-fwd-offload?
> diff --git a/include/linux/if_hsr.h b/include/linux/if_hsr.h
> new file mode 100644
> index 000000000000..eec9079efab0
> --- /dev/null
> +++ b/include/linux/if_hsr.h
> @@ -0,0 +1,22 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _LINUX_IF_HSR_H_
> +#define _LINUX_IF_HSR_H_
> +
> +/* used to differentiate various protocols */
> +enum hsr_version {
> + HSR_V0 = 0,
> + HSR_V1,
> + PRP_V1,
> +};
> +
> +#if IS_ENABLED(CONFIG_HSR)
> +extern int hsr_get_version(struct net_device *dev, enum hsr_version *ver);
> +#else
> +static inline int hsr_get_version(struct net_device *dev,
> + enum hsr_version *ver)
> +{
> + return -EINVAL;
> +}
> +#endif /* CONFIG_HSR */
> +
> +#endif /*_LINUX_IF_HSR_H_*/
> diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
> index c06d6aaba9df..3de38d6a0aea 100644
> --- a/include/linux/netdev_features.h
> +++ b/include/linux/netdev_features.h
> @@ -86,6 +86,11 @@ enum {
> NETIF_F_HW_MACSEC_BIT, /* Offload MACsec operations */
> NETIF_F_GRO_UDP_FWD_BIT, /* Allow UDP GRO for forwarding */
>
> + NETIF_F_HW_HSR_TAG_INS_BIT, /* Offload HSR tag insertion */
> + NETIF_F_HW_HSR_TAG_RM_BIT, /* Offload HSR tag removal */
> + NETIF_F_HW_HSR_FWD_BIT, /* Offload HSR forwarding */
> + NETIF_F_HW_HSR_DUP_BIT, /* Offload HSR duplication */
> +
> /*
> * Add your fresh new feature above and remember to update
> * netdev_features_strings[] in net/core/ethtool.c and maybe
> @@ -159,6 +164,10 @@ enum {
> #define NETIF_F_GSO_FRAGLIST __NETIF_F(GSO_FRAGLIST)
> #define NETIF_F_HW_MACSEC __NETIF_F(HW_MACSEC)
> #define NETIF_F_GRO_UDP_FWD __NETIF_F(GRO_UDP_FWD)
> +#define NETIF_F_HW_HSR_TAG_INS __NETIF_F(HW_HSR_TAG_INS)
> +#define NETIF_F_HW_HSR_TAG_RM __NETIF_F(HW_HSR_TAG_RM)
> +#define NETIF_F_HW_HSR_FWD __NETIF_F(HW_HSR_FWD)
> +#define NETIF_F_HW_HSR_DUP __NETIF_F(HW_HSR_DUP)
>
> /* Finds the next feature with the highest number of the range of start till
> 0.
> */
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index e9e7ada07ea1..9ac6f30c4a51 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -1526,6 +1526,7 @@ struct net_device_ops {
> * @IFF_FAILOVER_SLAVE: device is lower dev of a failover master device
> * @IFF_L3MDEV_RX_HANDLER: only invoke the rx handler of L3 master device
> * @IFF_LIVE_RENAME_OK: rename is allowed while device is up and running
> + * @IFF_HSR: device is an hsr device
> */
> enum netdev_priv_flags {
> IFF_802_1Q_VLAN = 1<<0,
> @@ -1559,6 +1560,7 @@ enum netdev_priv_flags {
> IFF_FAILOVER_SLAVE = 1<<28,
> IFF_L3MDEV_RX_HANDLER = 1<<29,
> IFF_LIVE_RENAME_OK = 1<<30,
> + IFF_HSR = 1<<31,
> };
>
> #define IFF_802_1Q_VLAN IFF_802_1Q_VLAN
> @@ -1591,6 +1593,7 @@ enum netdev_priv_flags {
> #define IFF_FAILOVER_SLAVE IFF_FAILOVER_SLAVE
> #define IFF_L3MDEV_RX_HANDLER IFF_L3MDEV_RX_HANDLER
> #define IFF_LIVE_RENAME_OK IFF_LIVE_RENAME_OK
> +#define IFF_HSR IFF_HSR
>
> /**
> * struct net_device - The DEVICE structure.
> @@ -5003,6 +5006,16 @@ static inline bool netif_is_failover_slave(const
> struct net_device *dev)
> return dev->priv_flags & IFF_FAILOVER_SLAVE;
> }
>
> +static inline bool netif_is_hsr_master(const struct net_device *dev)
> +{
> + return dev->flags & IFF_MASTER && dev->priv_flags & IFF_HSR;
> +}
> +
> +static inline bool netif_is_hsr_slave(const struct net_device *dev)
> +{
> + return dev->flags & IFF_SLAVE && dev->priv_flags & IFF_HSR;
> +}
> +
> /* This device needs to keep skb dst for qdisc enqueue or ndo_start_xmit() */
> static inline void netif_keep_dst(struct net_device *dev)
> {
> diff --git a/net/ethtool/common.c b/net/ethtool/common.c
> index 181220101a6e..0298e5635ace 100644
> --- a/net/ethtool/common.c
> +++ b/net/ethtool/common.c
> @@ -69,6 +69,10 @@ const char
> netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
> [NETIF_F_GRO_FRAGLIST_BIT] = "rx-gro-list",
> [NETIF_F_HW_MACSEC_BIT] = "macsec-hw-offload",
> [NETIF_F_GRO_UDP_FWD_BIT] = "rx-udp-gro-forwarding",
> + [NETIF_F_HW_HSR_TAG_INS_BIT] = "hsr-tag-ins-offload",
> + [NETIF_F_HW_HSR_TAG_RM_BIT] = "hsr-tag-rm-offload",
> + [NETIF_F_HW_HSR_FWD_BIT] = "hsr-fwd-offload",
> + [NETIF_F_HW_HSR_DUP_BIT] = "hsr-dup-offload",
> };
>
> const char
> diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
> index 161b8da6a21d..d9b033e9b18c 100644
> --- a/net/hsr/hsr_device.c
> +++ b/net/hsr/hsr_device.c
> @@ -418,6 +418,7 @@ static struct hsr_proto_ops hsr_ops = {
> .send_sv_frame = send_hsr_supervision_frame,
> .create_tagged_frame = hsr_create_tagged_frame,
> .get_untagged_frame = hsr_get_untagged_frame,
> + .drop_frame = hsr_drop_frame,
> .fill_frame_info = hsr_fill_frame_info,
> .invalid_dan_ingress_frame = hsr_invalid_dan_ingress_frame,
> };
> @@ -521,15 +522,8 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct
> net_device *slave[2],
>
> hsr->prot_version = protocol_version;
>
> - /* FIXME: should I modify the value of these?
> - *
> - * - hsr_dev->flags - i.e.
> - * IFF_MASTER/SLAVE?
> - * - hsr_dev->priv_flags - i.e.
> - * IFF_EBRIDGE?
> - * IFF_TX_SKB_SHARING?
> - * IFF_HSR_MASTER/SLAVE?
> - */
> + hsr_dev->flags |= IFF_MASTER;
> + hsr_dev->priv_flags |= IFF_HSR;
>
> /* Make sure the 1st call to netif_carrier_on() gets through */
> netif_carrier_off(hsr_dev);
> diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
> index a5566b2245a0..9c79d602c4e0 100644
> --- a/net/hsr/hsr_forward.c
> +++ b/net/hsr/hsr_forward.c
> @@ -247,6 +247,8 @@ struct sk_buff *hsr_create_tagged_frame(struct
> hsr_frame_info *frame,
> /* set the lane id properly */
> hsr_set_path_id(hsr_ethhdr, port);
> return skb_clone(frame->skb_hsr, GFP_ATOMIC);
> + } else if (port->dev->features & NETIF_F_HW_HSR_TAG_INS) {
> + return skb_clone(frame->skb_std, GFP_ATOMIC);
> }
>
> /* Create the new skb with enough headroom to fit the HSR tag */
> @@ -341,6 +343,14 @@ bool prp_drop_frame(struct hsr_frame_info *frame, struct
> hsr_port *port)
> port->type == HSR_PT_SLAVE_A));
> }
>
> +bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port)
> +{
> + if (port->dev->features & NETIF_F_HW_HSR_FWD)
> + return prp_drop_frame(frame, port);
> +
> + return false;
> +}
> +
> /* Forward the frame through all devices except:
> * - Back through the receiving device
> * - If it's a HSR frame: through a device where it has passed before
> @@ -357,6 +367,7 @@ static void hsr_forward_do(struct hsr_frame_info *frame)
> {
> struct hsr_port *port;
> struct sk_buff *skb;
> + bool sent = false;
>
> hsr_for_each_port(frame->port_rcv->hsr, port) {
> struct hsr_priv *hsr = port->hsr;
> @@ -372,6 +383,12 @@ static void hsr_forward_do(struct hsr_frame_info *frame)
> if (port->type != HSR_PT_MASTER && frame->is_local_exclusive)
> continue;
>
> + /* If hardware duplicate generation is enabled, only send out
> + * one port.
> + */
> + if ((port->dev->features & NETIF_F_HW_HSR_DUP) && sent)
> + continue;
> +
Is this right? It looks to me that you are not bypassing only duplicate
generation, but also duplicate elimination.
I think this is duplicate elimination:
/* Don't send frame over port where it has been sent before.
* Also fro SAN, this shouldn't be done.
*/
if (!frame->is_from_san &&
hsr_register_frame_out(port, frame->node_src,
frame->sequence_nr))
continue;
and this is duplicate generation:
hsr_for_each_port(frame->port_rcv->hsr, port) {
...
skb->dev = port->dev;
if (port->type == HSR_PT_MASTER)
hsr_deliver_master(skb, port->dev, frame->node_src);
else
hsr_xmit(skb, port, frame);
}
So if this is the description of NETIF_F_HW_HSR_DUP:
| Duplication involves the switch automatically sending a single frame
| from the CPU port to both redundant ports. This is required because the
| inserted HSR/PRP header/trailer must contain the same sequence number
| on the frames sent out both redundant ports.
then NETIF_F_HW_HSR_DUP is a misnomer. You should think of either
grouping duplicate elimination and generation together, or rethinking
the whole features system.
> /* Don't send frame over port where it has been sent before.
> * Also fro SAN, this shouldn't be done.
> */
> @@ -403,10 +420,12 @@ static void hsr_forward_do(struct hsr_frame_info *frame)
> }
>
> skb->dev = port->dev;
> - if (port->type == HSR_PT_MASTER)
> + if (port->type == HSR_PT_MASTER) {
> hsr_deliver_master(skb, port->dev, frame->node_src);
> - else
> - hsr_xmit(skb, port, frame);
> + } else {
> + if (!hsr_xmit(skb, port, frame))
> + sent = true;
> + }
> }
> }
>
> @@ -457,6 +476,7 @@ void hsr_fill_frame_info(__be16 proto, struct sk_buff
> *skb,
> struct hsr_port *port = frame->port_rcv;
>
> if (port->type != HSR_PT_MASTER &&
> + !(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
> (proto == htons(ETH_P_PRP) || proto == htons(ETH_P_HSR))) {
> /* HSR tagged frame :- Data or Supervision */
> frame->skb_std = NULL;
> @@ -478,6 +498,7 @@ void prp_fill_frame_info(__be16 proto, struct sk_buff
> *skb,
> struct hsr_port *port = frame->port_rcv;
>
> if (port->type != HSR_PT_MASTER &&
> + !(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
> rct &&
> prp_check_lsdu_size(skb, rct, frame->is_supervision)) {
> frame->skb_hsr = NULL;
> diff --git a/net/hsr/hsr_forward.h b/net/hsr/hsr_forward.h
> index 618140d484ad..b6acaafa83fc 100644
> --- a/net/hsr/hsr_forward.h
> +++ b/net/hsr/hsr_forward.h
> @@ -23,6 +23,7 @@ struct sk_buff *hsr_get_untagged_frame(struct
> hsr_frame_info *frame,
> struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame,
> struct hsr_port *port);
> bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port);
> +bool hsr_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port);
> void prp_fill_frame_info(__be16 proto, struct sk_buff *skb,
> struct hsr_frame_info *frame);
> void hsr_fill_frame_info(__be16 proto, struct sk_buff *skb,
> diff --git a/net/hsr/hsr_main.c b/net/hsr/hsr_main.c
> index 2fd1976e5b1c..0e7b5b18b5e3 100644
> --- a/net/hsr/hsr_main.c
> +++ b/net/hsr/hsr_main.c
> @@ -131,6 +131,20 @@ struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr,
> enum hsr_port_type pt)
> return NULL;
> }
>
> +int hsr_get_version(struct net_device *dev, enum hsr_version *ver)
> +{
> + struct hsr_priv *hsr;
> +
> + if (!(dev->priv_flags & IFF_HSR))
> + return -EINVAL;
> +
> + hsr = netdev_priv(dev);
> + *ver = hsr->prot_version;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(hsr_get_version);
> +
> static struct notifier_block hsr_nb = {
> .notifier_call = hsr_netdev_notify, /* Slave event notifications */
> };
> diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h
> index 7dc92ce5a134..7369b2febe0f 100644
> --- a/net/hsr/hsr_main.h
> +++ b/net/hsr/hsr_main.h
> @@ -13,6 +13,7 @@
> #include <linux/netdevice.h>
> #include <linux/list.h>
> #include <linux/if_vlan.h>
> +#include <linux/if_hsr.h>
>
> /* Time constants as specified in the HSR specification (IEC-62439-3 2010)
> * Table 8.
> @@ -171,13 +172,6 @@ struct hsr_port {
> enum hsr_port_type type;
> };
>
> -/* used by driver internally to differentiate various protocols */
> -enum hsr_version {
> - HSR_V0 = 0,
> - HSR_V1,
> - PRP_V1,
> -};
> -
> struct hsr_frame_info;
> struct hsr_node;
>
> diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c
> index 36d5fcf09c61..59f8d2b68376 100644
> --- a/net/hsr/hsr_slave.c
> +++ b/net/hsr/hsr_slave.c
> @@ -48,12 +48,14 @@ static rx_handler_result_t hsr_handle_frame(struct
> sk_buff **pskb)
> goto finish_consume;
> }
>
> - /* For HSR, only tagged frames are expected, but for PRP
> - * there could be non tagged frames as well from Single
> - * attached nodes (SANs).
> + /* For HSR, only tagged frames are expected (unless the device offloads
> + * HSR tag removal), but for PRP there could be non tagged frames as
> + * well from Single attached nodes (SANs).
> */
> protocol = eth_hdr(skb)->h_proto;
> - if (hsr->proto_ops->invalid_dan_ingress_frame &&
> +
> + if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
> + hsr->proto_ops->invalid_dan_ingress_frame &&
> hsr->proto_ops->invalid_dan_ingress_frame(protocol))
> goto finish_pass;
>
> @@ -137,6 +139,9 @@ static int hsr_portdev_setup(struct hsr_priv *hsr, struct
> net_device *dev,
> master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
> hsr_dev = master->dev;
>
> + dev->flags |= IFF_SLAVE;
> + dev->priv_flags |= IFF_HSR;
> +
> res = netdev_upper_dev_link(dev, hsr_dev, extack);
> if (res)
> goto fail_upper_dev_link;
> --
> 2.11.0
>
