ethtool: Symmetric OR-XOR RSS hash

Add an additional type of symmetric RSS hash type: OR-XOR.
The "Symmetric-OR-XOR" algorithm transforms the input as follows:

(SRC_IP | DST_IP, SRC_IP ^ DST_IP, SR

ethtool: Symmetric OR-XOR RSS hash

Add an additional type of symmetric RSS hash type: OR-XOR.
The "Symmetric-OR-XOR" algorithm transforms the input as follows:

(SRC_IP | DST_IP, SRC_IP ^ DST_IP, SRC_PORT | DST_PORT, SRC_PORT ^ DST_PORT)

Change 'cap_rss_sym_xor_supported' to 'supported_input_xfrm', a bitmap
of supported RXH_XFRM_* types.

Reviewed-by: Cosmin Ratiu <[email protected]>
Reviewed-by: Tariq Toukan <[email protected]>
Signed-off-by: Gal Pressman <[email protected]>
Reviewed-by: Edward Cree <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: ethtool: tsconfig: Fix netlink type of hwtstamp flags

Fix the netlink type for hardware timestamp flags, which are represented
as a bitset of flags. Although only one flag is supported currentl

net: ethtool: tsconfig: Fix netlink type of hwtstamp flags

Fix the netlink type for hardware timestamp flags, which are represented
as a bitset of flags. Although only one flag is supported currently, the
correct netlink bitset type should be used instead of u32 to keep
consistency with other fields. Address this by adding a new named string
set description for the hwtstamp flag structure.

The code has been introduced in the current release so the uAPI change is
still okay.

Signed-off-by: Kory Maincent <[email protected]>
Fixes: 6e9e2eed4f39 ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config")
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

ethtool: Add support for 200Gbps per lane link modes

Define 200G, 400G and 800G link modes using 200Gbps per lane.

Signed-off-by: Jianbo Liu <[email protected]>
Reviewed-by: Shahar Shitrit <shshit

ethtool: Add support for 200Gbps per lane link modes

Define 200G, 400G and 800G link modes using 200Gbps per lane.

Signed-off-by: Jianbo Liu <[email protected]>
Reviewed-by: Shahar Shitrit <[email protected]>
Signed-off-by: Tariq Toukan <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

show more ...

net: ethtool: add support for structured PHY statistics

Introduce a new way to report PHY statistics in a structured and
standardized format using the netlink API. This new method does not
replace t

net: ethtool: add support for structured PHY statistics

Introduce a new way to report PHY statistics in a structured and
standardized format using the netlink API. This new method does not
replace the old driver-specific stats, which can still be accessed with
`ethtool -S <eth name>`. The structured stats are available with
`ethtool -S <eth name> --all-groups`.

This new method makes it easier to diagnose problems by organizing stats
in a consistent and documented way.

Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Oleksij Rempel <[email protected]>
Signed-off-by: Paolo Abeni <[email protected]>

show more ...

UAPI: ethtool: Avoid flex-array in struct ethtool_link_settings

struct ethtool_link_settings tends to be used as a header for other
structures that have trailing bytes[1], but has a trailing flexibl

UAPI: ethtool: Avoid flex-array in struct ethtool_link_settings

struct ethtool_link_settings tends to be used as a header for other
structures that have trailing bytes[1], but has a trailing flexible array
itself. Using this overlapped with other structures leads to ambiguous
object sizing in the compiler, so we want to avoid such situations (which
have caused real bugs in the past). Detecting this can be done with
-Wflex-array-member-not-at-end, which will need to be enabled globally.

Using a tagged struct_group() to create a new ethtool_link_settings_hdr
structure isn't possible as it seems we cannot use the tagged variant of
struct_group() due to syntax issues from C++'s perspective (even within
"extern C")[2]. Instead, we can just leave the offending member defined
in UAPI and remove it from the kernel's view of the structure, as Linux
doesn't actually use this member at all. There is also no change in
size since it was already a flexible array that didn't contribute to
size returned by any use of sizeof().

Reported-by: Jakub Kicinski <[email protected]>
Closes: https://lore.kernel.org/lkml/[email protected]/ [2]
Link: https://lore.kernel.org/lkml/0bc2809fe2a6c11dd4c8a9a10d9bd65cccdb559b.1730238285.git.gustavoars@kernel.org/ [1]
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Jakub Kicinski <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

Revert "UAPI: ethtool: Use __struct_group() in struct ethtool_link_settings"

This reverts commit 43d3487035e9a86fad952de4240a518614240d43. We cannot
use tagged struct groups in UAPI because C++ will

Revert "UAPI: ethtool: Use __struct_group() in struct ethtool_link_settings"

This reverts commit 43d3487035e9a86fad952de4240a518614240d43. We cannot
use tagged struct groups in UAPI because C++ will throw syntax errors
even under "extern C".

Signed-off-by: Kees Cook <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

UAPI: ethtool: Use __struct_group() in struct ethtool_link_settings

Use the `__struct_group()` helper to create a new tagged
`struct ethtool_link_settings_hdr`. This structure groups together
all th

UAPI: ethtool: Use __struct_group() in struct ethtool_link_settings

Use the `__struct_group()` helper to create a new tagged
`struct ethtool_link_settings_hdr`. This structure groups together
all the members of the flexible `struct ethtool_link_settings`
except the flexible array. As a result, the array is effectively
separated from the rest of the members without modifying the memory
layout of the flexible structure.

This new tagged struct will be used to fix problematic declarations
of middle-flex-arrays in composite structs[1].

[1] https://git.kernel.org/linus/d88cabfd9abc

Signed-off-by: Gustavo A. R. Silva <[email protected]>
Link: https://patch.msgid.link/9e9fb0bd72e5ba1e916acbb4995b1e358b86a689.1730238285.git.gustavoars@kernel.org
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use
with an SFP connector, on which an SFP transceiver containing a PHY can
be used.

With the current model, the transceiver's PHY can't be used for
operations such as cable testing, timestamping, macsec offload, etc.

The reason being that most of the logic for these configuration, coming
from either ethtool netlink or ioctls tend to use netdev->phydev, which
in multi-phy systems will reference the PHY closest to the MAC.

Introduce a numbering scheme allowing to enumerate PHY devices that
belong to any netdev, which can in turn allow userspace to take more
precise decisions with regard to each PHY's configuration.

The numbering is maintained per-netdev, in a phy_device_list.
The numbering works similarly to a netdevice's ifindex, with
identifiers that are only recycled once INT_MAX has been reached.

This prevents races that could occur between PHY listing and SFP
transceiver removal/insertion.

The identifiers are assigned at phy_attach time, as the numbering
depends on the netdevice the phy is attached to. The PHY index can be
re-used for PHYs that are persistent.

Signed-off-by: Maxime Chevallier <[email protected]>
Reviewed-by: Christophe Leroy <[email protected]>
Tested-by: Christophe Leroy <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: phy: bcm54811: New link mode for BroadR-Reach

Introduce a new link mode necessary for 10 MBit single-pair
connection in BroadR-Reach mode on bcm5481x PHY by Broadcom.
This new link mode, 10base

net: phy: bcm54811: New link mode for BroadR-Reach

Introduce a new link mode necessary for 10 MBit single-pair
connection in BroadR-Reach mode on bcm5481x PHY by Broadcom.
This new link mode, 10baseT1BRR, is known as 1BR10 in the Broadcom
terminology. Another link mode to be used is 1BR100 and it is already
present as 100baseT1, because Broadcom's 1BR100 became 100baseT1
(IEEE 802.3bw).

Signed-off-by: Kamil Horák (2N) <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: ethtool: pse-pd: Expand C33 PSE status with class, power and extended state

This update expands the status information provided by ethtool for PSE c33.
It includes details such as the detected

net: ethtool: pse-pd: Expand C33 PSE status with class, power and extended state

This update expands the status information provided by ethtool for PSE c33.
It includes details such as the detected class, current power delivered,
and extended state information.

Reviewed-by: Oleksij Rempel <[email protected]>
Signed-off-by: Kory Maincent <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

ethtool: Add an interface for flashing transceiver modules' firmware

CMIS compliant modules such as QSFP-DD might be running a firmware that
can be updated in a vendor-neutral way by exchanging mess

ethtool: Add an interface for flashing transceiver modules' firmware

CMIS compliant modules such as QSFP-DD might be running a firmware that
can be updated in a vendor-neutral way by exchanging messages between
the host and the module as described in section 7.3.1 of revision 5.2 of
the CMIS standard.

Add a pair of new ethtool messages that allow:

* User space to trigger firmware update of transceiver modules

* The kernel to notify user space about the progress of the process

The user interface is designed to be asynchronous in order to avoid
RTNL being held for too long and to allow several modules to be
updated simultaneously. The interface is designed with CMIS compliant
modules in mind, but kept generic enough to accommodate future use
cases, if these arise.

Signed-off-by: Danielle Ratson <[email protected]>
Reviewed-by: Petr Machata <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: revert partially applied PHY topology series

The series is causing issues with PHY drivers built as modules.
Since it was only partially applied and the merge window has
opened let's revert and

net: revert partially applied PHY topology series

The series is causing issues with PHY drivers built as modules.
Since it was only partially applied and the merge window has
opened let's revert and try again for v6.11.

Revert 6916e461e793 ("net: phy: Introduce ethernet link topology representation")
Revert 0ec5ed6c130e ("net: sfp: pass the phy_device when disconnecting an sfp module's PHY")
Revert e75e4e074c44 ("net: phy: add helpers to handle sfp phy connect/disconnect")
Revert fdd353965b52 ("net: sfp: Add helper to return the SFP bus name")
Revert 841942bc6212 ("net: ethtool: Allow passing a phy index for some commands")

Link: https://lore.kernel.org/all/171242462917.4000.9759453824684907063.git-patchwork-notify@kernel.org/
Link: https://lore.kernel.org/all/[email protected]/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: pse-pd: Introduce PSE types enumeration

Introduce an enumeration to define PSE types (C33 or PoDL),
utilizing a bitfield for potential future support of both types.
Include 'pse_get_types' help

net: pse-pd: Introduce PSE types enumeration

Introduce an enumeration to define PSE types (C33 or PoDL),
utilizing a bitfield for potential future support of both types.
Include 'pse_get_types' helper for external access to PSE type info.

Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: Kory Maincent <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

ethtool: Expand Ethernet Power Equipment with c33 (PoE) alongside PoDL

In the current PSE interface for Ethernet Power Equipment, support is
limited to PoDL. This patch extends the interface to acco

ethtool: Expand Ethernet Power Equipment with c33 (PoE) alongside PoDL

In the current PSE interface for Ethernet Power Equipment, support is
limited to PoDL. This patch extends the interface to accommodate the
objects specified in IEEE 802.3-2022 145.2 for Power sourcing
Equipment (PSE).

The following objects are now supported and considered mandatory:
- IEEE 802.3-2022 30.9.1.1.5 aPSEPowerDetectionStatus
- IEEE 802.3-2022 30.9.1.1.2 aPSEAdminState
- IEEE 802.3-2022 30.9.1.2.1 aPSEAdminControl

To avoid confusion between "PoDL PSE" and "PoE PSE", which have similar
names but distinct values, we have followed the suggestion of Oleksij
Rempel and Andrew Lunn to maintain separate naming schemes for each,
using c33 (clause 33) prefix for "PoE PSE".
You can find more details in the discussion threads here:
https://lore.kernel.org/netdev/[email protected]/
https://lore.kernel.org/netdev/[email protected]/

Reviewed-by: Andrew Lunn <[email protected]>
Reviewed-by: Oleksij Rempel <[email protected]>
Signed-off-by: Kory Maincent <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use
with an SFP connector, on which an SFP transceiver containing a PHY can
be used.

With the current model, the transceiver's PHY can't be used for
operations such as cable testing, timestamping, macsec offload, etc.

The reason being that most of the logic for these configuration, coming
from either ethtool netlink or ioctls tend to use netdev->phydev, which
in multi-phy systems will reference the PHY closest to the MAC.

Introduce a numbering scheme allowing to enumerate PHY devices that
belong to any netdev, which can in turn allow userspace to take more
precise decisions with regard to each PHY's configuration.

The numbering is maintained per-netdev, in a phy_device_list.
The numbering works similarly to a netdevice's ifindex, with
identifiers that are only recycled once INT_MAX has been reached.

This prevents races that could occur between PHY listing and SFP
transceiver removal/insertion.

The identifiers are assigned at phy_attach time, as the numbering
depends on the netdevice the phy is attached to. The PHY index can be
re-used for PHYs that are persistent.

Signed-off-by: Maxime Chevallier <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ethtool: Add GTP RSS hash options to ethtool.h

This is a patch that enables RSS functionality for GTP packets using ethtool.

A user can include TEID and make RSS work for GTP-U over IPv4 by doing t

ethtool: Add GTP RSS hash options to ethtool.h

This is a patch that enables RSS functionality for GTP packets using ethtool.

A user can include TEID and make RSS work for GTP-U over IPv4 by doing the
following:`ethtool -N ens3 rx-flow-hash gtpu4 sde`

In addition to gtpu(4|6), we now support gtpc(4|6),gtpc(4|6)t,gtpu(4|6)e,
gtpu(4|6)u, and gtpu(4|6)d.

gtpc(4|6): Used for GTP-C in IPv4 and IPv6, where the GTP header format does
not include a TEID.
gtpc(4|6)t: Used for GTP-C in IPv4 and IPv6, with a GTP header format that
includes a TEID.
gtpu(4|6): Used for GTP-U in both IPv4 and IPv6 scenarios.
gtpu(4|6)e: Used for GTP-U with extended headers in both IPv4 and IPv6.
gtpu(4|6)u: Used when the PSC (PDU session container) in the GTP-U extended
header includes Uplink, applicable to both IPv4 and IPv6.
gtpu(4|6)d: Used when the PSC in the GTP-U extended header includes Downlink,
for both IPv4 and IPv6.

GTP generates a flow that includes an ID called TEID to identify the tunnel.
This tunnel is created for each UE (User Equipment).By performing RSS based on
this flow, it is possible to apply RSS for each communication unit from the UE.
Without this, RSS would only be effective within the range of IP addresses. For
instance, the PGW can only perform RSS within the IP range of the SGW.
Problematic from a load distribution perspective, especially if there's a bias
in the terminals connected to a particular base station.This case can be
solved by using this patch.

Signed-off-by: Takeru Hayasaka <[email protected]>
Reviewed-by: Marcin Szycik <[email protected]>
Tested-by: Pucha Himasekhar Reddy <[email protected]> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <[email protected]>

show more ...

Revert "Introduce PHY listing and link_topology tracking"

This reverts commit 32bb4515e34469975abc936deb0a116c4a445817.
This reverts commit d078d480639a4f3b5fc2d56247afa38e0956483a.
This reverts com

Revert "Introduce PHY listing and link_topology tracking"

This reverts commit 32bb4515e34469975abc936deb0a116c4a445817.
This reverts commit d078d480639a4f3b5fc2d56247afa38e0956483a.
This reverts commit fcc4b105caa4b844bf043375bf799c20a9c99db1.
This reverts commit 345237dbc1bdbb274c9fb9ec38976261ff4a40b8.
This reverts commit 7db69ec9cfb8b4ab50420262631fb2d1908b25bf.
This reverts commit 95132a018f00f5dad38bdcfd4180d1af955d46f6.
This reverts commit 63d5eaf35ac36cad00cfb3809d794ef0078c822b.
This reverts commit c29451aefcb42359905d18678de38e52eccb3bb5.
This reverts commit 2ab0edb505faa9ac90dee1732571390f074e8113.
This reverts commit dedd702a35793ab462fce4c737eeba0badf9718e.
This reverts commit 034fcc210349b873ece7356905be5c6ca11eef2a.
This reverts commit 9c5625f559ad6fe9f6f733c11475bf470e637d34.
This reverts commit 02018c544ef113e980a2349eba89003d6f399d22.

Looks like we need more time for reviews, and incremental
changes will be hard to make sense of. So revert.

Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: ethtool: add a NO_CHANGE uAPI for new RXFH's input_xfrm

Add a NO_CHANGE uAPI value for the new RXFH/RSS input_xfrm uAPI field.
This needed so that user-space can set other RSS values (hkey or i

net: ethtool: add a NO_CHANGE uAPI for new RXFH's input_xfrm

Add a NO_CHANGE uAPI value for the new RXFH/RSS input_xfrm uAPI field.
This needed so that user-space can set other RSS values (hkey or indir
table) without affecting input_xfrm.

Should have been part of [1].

Link: https://lore.kernel.org/netdev/[email protected]/ [1]
Fixes: 13e59344fb9d ("net: ethtool: add support for symmetric-xor RSS hash")
Reviewed-by: Jacob Keller <[email protected]>
Signed-off-by: Ahmed Zaki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

show more ...

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use

net: phy: Introduce ethernet link topology representation

Link topologies containing multiple network PHYs attached to the same
net_device can be found when using a PHY as a media converter for use
with an SFP connector, on which an SFP transceiver containing a PHY can
be used.

With the current model, the transceiver's PHY can't be used for
operations such as cable testing, timestamping, macsec offload, etc.

The reason being that most of the logic for these configuration, coming
from either ethtool netlink or ioctls tend to use netdev->phydev, which
in multi-phy systems will reference the PHY closest to the MAC.

Introduce a numbering scheme allowing to enumerate PHY devices that
belong to any netdev, which can in turn allow userspace to take more
precise decisions with regard to each PHY's configuration.

The numbering is maintained per-netdev, in a phy_device_list.
The numbering works similarly to a netdevice's ifindex, with
identifiers that are only recycled once INT_MAX has been reached.

This prevents races that could occur between PHY listing and SFP
transceiver removal/insertion.

The identifiers are assigned at phy_attach time, as the numbering
depends on the netdevice the phy is attached to.

Signed-off-by: Maxime Chevallier <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

ethtool: reformat kerneldoc for struct ethtool_link_settings

The kernel doc comments for struct ethtool_link_settings includes
documentation for three fields that were never present there, leading t

ethtool: reformat kerneldoc for struct ethtool_link_settings

The kernel doc comments for struct ethtool_link_settings includes
documentation for three fields that were never present there, leading to
these docs-build warnings:

./include/uapi/linux/ethtool.h:2207: warning: Excess struct member 'supported' description in 'ethtool_link_settings'
./include/uapi/linux/ethtool.h:2207: warning: Excess struct member 'advertising' description in 'ethtool_link_settings'
./include/uapi/linux/ethtool.h:2207: warning: Excess struct member 'lp_advertising' description in 'ethtool_link_settings'

Remove the entries to make the warnings go away. There was some
information there on how data in >link_mode_masks is formatted; move that
to the body of the comment to preserve it.

Signed-off-by: Jonathan Corbet <[email protected]>
Reviewed-by: Randy Dunlap <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: ethtool: add support for symmetric-xor RSS hash

Symmetric RSS hash functions are beneficial in applications that monitor
both Tx and Rx packets of the same flow (IDS, software firewalls, ..etc)

net: ethtool: add support for symmetric-xor RSS hash

Symmetric RSS hash functions are beneficial in applications that monitor
both Tx and Rx packets of the same flow (IDS, software firewalls, ..etc).
Getting all traffic of the same flow on the same RX queue results in
higher CPU cache efficiency.

A NIC that supports "symmetric-xor" can achieve this RSS hash symmetry
by XORing the source and destination fields and pass the values to the
RSS hash algorithm.

The user may request RSS hash symmetry for a specific algorithm, via:

# ethtool -X eth0 hfunc <hash_alg> symmetric-xor

or turn symmetry off (asymmetric) by:

# ethtool -X eth0 hfunc <hash_alg>

The specific fields for each flow type should then be specified as usual
via:
# ethtool -N|-U eth0 rx-flow-hash <flow_type> s|d|f|n

Reviewed-by: Wojciech Drewek <[email protected]>
Signed-off-by: Ahmed Zaki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

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net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)

IEEE 802.3-2018 clause 99 defines a MAC Merge sublayer which contains an
Express MAC and a Preemptible MAC. Both MACs are hid

net: ethtool: netlink: retrieve stats from multiple sources (eMAC, pMAC)

IEEE 802.3-2018 clause 99 defines a MAC Merge sublayer which contains an
Express MAC and a Preemptible MAC. Both MACs are hidden to higher and
lower layers and visible as a single MAC (packet classification to eMAC
or pMAC on TX is done based on priority; classification on RX is done
based on SFD).

For devices which support a MAC Merge sublayer, it is desirable to
retrieve individual packet counters from the eMAC and the pMAC, as well
as aggregate statistics (their sum).

Introduce a new ETHTOOL_A_STATS_SRC attribute which is part of the
policy of ETHTOOL_MSG_STATS_GET and, and an ETHTOOL_A_PAUSE_STATS_SRC
which is part of the policy of ETHTOOL_MSG_PAUSE_GET (accepted when
ETHTOOL_FLAG_STATS is set in the common ethtool header). Both of these
take values from enum ethtool_mac_stats_src, defaulting to "aggregate"
in the absence of the attribute.

Existing drivers do not need to pay attention to this enum which was
added to all driver-facing structures, just the ones which report the
MAC merge layer as supported.

Signed-off-by: Vladimir Oltean <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

show more ...

net: ethtool: add support for MAC Merge layer

The MAC merge sublayer (IEEE 802.3-2018 clause 99) is one of 2
specifications (the other being Frame Preemption; IEEE 802.1Q-2018
clause 6.7.2), which w

net: ethtool: add support for MAC Merge layer

The MAC merge sublayer (IEEE 802.3-2018 clause 99) is one of 2
specifications (the other being Frame Preemption; IEEE 802.1Q-2018
clause 6.7.2), which work together to minimize latency caused by frame
interference at TX. The overall goal of TSN is for normal traffic and
traffic with a bounded deadline to be able to cohabitate on the same L2
network and not bother each other too much.

The standards achieve this (partly) by introducing the concept of
preemptible traffic, i.e. Ethernet frames that have a custom value for
the Start-of-Frame-Delimiter (SFD), and these frames can be fragmented
and reassembled at L2 on a link-local basis. The non-preemptible frames
are called express traffic, they are transmitted using a normal SFD, and
they can preempt preemptible frames, therefore having lower latency,
which can matter at lower (100 Mbps) link speeds, or at high MTUs (jumbo
frames around 9K). Preemption is not recursive, i.e. a P frame cannot
preempt another P frame. Preemption also does not depend upon priority,
or otherwise said, an E frame with prio 0 will still preempt a P frame
with prio 7.

In terms of implementation, the standards talk about the presence of an
express MAC (eMAC) which handles express traffic, and a preemptible MAC
(pMAC) which handles preemptible traffic, and these MACs are multiplexed
on the same MII by a MAC merge layer.

To support frame preemption, the definition of the SFD was generalized
to SMD (Start-of-mPacket-Delimiter), where an mPacket is essentially an
Ethernet frame fragment, or a complete frame. Stations unaware of an SMD
value different from the standard SFD will treat P frames as error
frames. To prevent that from happening, a negotiation process is
defined.

On RX, packets are dispatched to the eMAC or pMAC after being filtered
by their SMD. On TX, the eMAC/pMAC classification decision is taken by
the 802.1Q spec, based on packet priority (each of the 8 user priority
values may have an admin-status of preemptible or express).

The MAC Merge layer and the Frame Preemption parameters have some degree
of independence in terms of how software stacks are supposed to deal
with them. The activation of the MM layer is supposed to be controlled
by an LLDP daemon (after it has been communicated that the link partner
also supports it), after which a (hardware-based or not) verification
handshake takes place, before actually enabling the feature. So the
process is intended to be relatively plug-and-play. Whereas FP settings
are supposed to be coordinated across a network using something
approximating NETCONF.

The support contained here is exclusively for the 802.3 (MAC Merge)
portions and not for the 802.1Q (Frame Preemption) parts. This API is
sufficient for an LLDP daemon to do its job. The FP adminStatus variable
from 802.1Q is outside the scope of an LLDP daemon.

I have taken a few creative licenses and augmented the Linux kernel UAPI
compared to the standard managed objects recommended by IEEE 802.3.
These are:

- ETHTOOL_A_MM_PMAC_ENABLED: According to Figure 99-6: Receive
Processing state diagram, a MAC Merge layer is always supposed to be
able to receive P frames. However, this implies keeping the pMAC
powered on, which will consume needless power in applications where FP
will never be used. If LLDP is used, the reception of an Additional
Ethernet Capabilities TLV from the link partner is sufficient
indication that the pMAC should be enabled. So my proposal is that in
Linux, we keep the pMAC turned off by default and that user space
turns it on when needed.

- ETHTOOL_A_MM_VERIFY_ENABLED: The IEEE managed object is called
aMACMergeVerifyDisableTx. I opted for consistency (positive logic) in
the boolean netlink attributes offered, so this is also positive here.
Other than the meaning being reversed, they correspond to the same
thing.

- ETHTOOL_A_MM_MAX_VERIFY_TIME: I found it most reasonable for a LLDP
daemon to maximize the verifyTime variable (delay between SMD-V
transmissions), to maximize its chances that the LP replies. IEEE says
that the verifyTime can range between 1 and 128 ms, but the NXP ENETC
stupidly keeps this variable in a 7 bit register, so the maximum
supported value is 127 ms. I could have chosen to hardcode this in the
LLDP daemon to a lower value, but why not let the kernel expose its
supported range directly.

- ETHTOOL_A_MM_TX_MIN_FRAG_SIZE: the standard managed object is called
aMACMergeAddFragSize, and expresses the "additional" fragment size
(on top of ETH_ZLEN), whereas this expresses the absolute value of the
fragment size.

- ETHTOOL_A_MM_RX_MIN_FRAG_SIZE: there doesn't appear to exist a managed
object mandated by the standard, but user space clearly needs to know
what is the minimum supported fragment size of our local receiver,
since LLDP must advertise a value no lower than that.

Signed-off-by: Vladimir Oltean <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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drivers/net/phy: add the link modes for the 10BASE-T1S Ethernet PHY

This patch adds the link modes for the IEEE 802.3cg Clause 147 10BASE-T1S
Ethernet PHY. According to the specifications, the 10BAS

drivers/net/phy: add the link modes for the 10BASE-T1S Ethernet PHY

This patch adds the link modes for the IEEE 802.3cg Clause 147 10BASE-T1S
Ethernet PHY. According to the specifications, the 10BASE-T1S supports
Point-To-Point Full-Duplex, Point-To-Point Half-Duplex and/or
Point-To-Multipoint (AKA Multi-Drop) Half-Duplex operations.

Signed-off-by: Piergiorgio Beruto <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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ethtool: Replace 0-length array with flexible array

Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's
"rule_locs" 0-length array with a flexible array. Detected with GCC 13,
using

ethtool: Replace 0-length array with flexible array

Zero-length arrays are deprecated[1]. Replace struct ethtool_rxnfc's
"rule_locs" 0-length array with a flexible array. Detected with GCC 13,
using -fstrict-flex-arrays=3:

net/ethtool/common.c: In function 'ethtool_get_max_rxnfc_channel':
net/ethtool/common.c:558:55: warning: array subscript i is outside array bounds of '__u32[0]' {aka 'unsigned int[]'} [-Warray-bounds=]
558 | .fs.location = info->rule_locs[i],
| ~~~~~~~~~~~~~~~^~~
In file included from include/linux/ethtool.h:19,
from include/uapi/linux/ethtool_netlink.h:12,
from include/linux/ethtool_netlink.h:6,
from net/ethtool/common.c:3:
include/uapi/linux/ethtool.h:1186:41: note: while referencing
'rule_locs'
1186 | __u32 rule_locs[0];
| ^~~~~~~~~

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Cc: Andrew Lunn <[email protected]>
Cc: kernel test robot <[email protected]>
Cc: Oleksij Rempel <[email protected]>
Cc: Sean Anderson <[email protected]>
Cc: Alexandru Tachici <[email protected]>
Cc: Amit Cohen <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Vincent Mailhol <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

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