RE: [PATCH v2 net-next 02/12] net: ethtool: add support for MAC Merge layer

From: Somisetty, Pranavi
Date: Mon Jan 16 2023 - 04:06:29 EST



> -----Original Message-----
> From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> Sent: Wednesday, January 11, 2023 9:47 PM
> To: netdev@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx; David S. Miller <davem@xxxxxxxxxxxxx>;
> Eric Dumazet <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>;
> Paolo Abeni <pabeni@xxxxxxxxxx>; Michal Kubecek <mkubecek@xxxxxxx>;
> Claudiu Manoil <claudiu.manoil@xxxxxxx>; Vinicius Costa Gomes
> <vinicius.gomes@xxxxxxxxx>; Xiaoliang Yang <xiaoliang.yang_1@xxxxxxx>;
> Kurt Kanzenbach <kurt@xxxxxxxxxxxxx>; Rui Sousa <rui.sousa@xxxxxxx>;
> Ferenc Fejes <ferenc.fejes@xxxxxxxxxxxx>; Somisetty, Pranavi
> <pranavi.somisetty@xxxxxxx>; Katakam, Harini
> <harini.katakam@xxxxxxx>; Colin Foster <colin.foster@xxxxxxxxxxxxxxxx>;
> UNGLinuxDriver@xxxxxxxxxxxxx; Alexandre Belloni
> <alexandre.belloni@xxxxxxxxxxx>; Andrew Lunn <andrew@xxxxxxx>; Florian
> Fainelli <f.fainelli@xxxxxxxxx>
> Subject: [PATCH v2 net-next 02/12] 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.
>
> Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> ---
> v1->v2:
> - added documentation
> - introduced pmac_enabled
> - transformed verify_disable into verify_enabled
> - made add_frag_size take a value in octets
> - removed FP params (adminStatus)
> - renamed "enabled" to "tx_enabled" and "active" to "tx_active"
>
> include/linux/ethtool.h | 99 ++++++++++
> include/uapi/linux/ethtool.h | 25 +++
> include/uapi/linux/ethtool_netlink.h | 47 +++++
> net/ethtool/Makefile | 4 +-
> net/ethtool/mm.c | 258 +++++++++++++++++++++++++++
> net/ethtool/netlink.c | 19 ++
> net/ethtool/netlink.h | 4 +
> 7 files changed, 454 insertions(+), 2 deletions(-) create mode 100644
> net/ethtool/mm.c
>
> diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h index
> 9e0a76fc7de9..6336f105e667 100644
> --- a/include/linux/ethtool.h
> +++ b/include/linux/ethtool.h
> @@ -467,6 +467,98 @@ struct ethtool_module_power_mode_params {
> enum ethtool_module_power_mode mode;
> };
>
> +/**
> + * struct ethtool_mm_state - 802.3 MAC merge layer state
> + * @verify_time:
> + * wait time between verification attempts in ms (according to clause
> + * 30.14.1.6 aMACMergeVerifyTime)
> + * @max_verify_time:
> + * maximum accepted value for the @verify_time variable in set
> requests
> + * @verify_status:
> + * state of the verification state machine of the MM layer (according to
> + * clause 30.14.1.2 aMACMergeStatusVerify)
> + * @supported:
> + * set if device supports the MM layer (according to clause 30.14.1.1
> + * aMACMergeSupport)
> + * @tx_enabled:
> + * set if the MM layer is administratively enabled in the TX direction
> + * (according to clause 30.14.1.3 aMACMergeEnableTx)
> + * @tx_active:
> + * set if the MM layer is enabled in the TX direction, which makes FP
> + * possible (according to 30.14.1.5 aMACMergeStatusTx). This should
> be
> + * true if MM is enabled, and the verification status is either verified,
> + * or disabled.
> + * @pmac_enabled:
> + * set if the preemptible MAC is powered on and is able to receive
> + * preemptible packets and respond to verification frames.
> + * @verify_enabled:
> + * set if the Verify function of the MM layer (which sends SMD-V
> + * verification requests) is administratively enabled (regardless of
> + * whether it is currently in the
> ETHTOOL_MM_VERIFY_STATUS_DISABLED state
> + * or not), according to clause 30.14.1.4 aMACMergeVerifyDisableTx
> (but
> + * using positive rather than negative logic). The device should always
> + * respond to received SMD-V requests as long as @pmac_enabled is
> set.
> + * @add_frag_size:
> + * the minimum size of non-final mPacket fragments that the link
> partner
> + * supports receiving, expressed in octets. Compared to the definition
> + * from clause 30.14.1.7 aMACMergeAddFragSize which is expressed in
> the
> + * range 0 to 3 (requiring a translation to the size in octets according
> + * to the formula 64 * (1 + addFragSize) – 4), a value in a continuous
> and
> + * unbounded range can be specified here.
> + */
> +struct ethtool_mm_state {
> + u32 verify_time;
> + u32 max_verify_time;
> + enum ethtool_mm_verify_status verify_status;
> + bool supported;
> + bool tx_enabled;
> + bool tx_active;
> + bool pmac_enabled;
> + bool verify_enabled;
> + u32 add_frag_size;
> +};
> +
> +/**
> + * struct ethtool_mm_cfg - 802.3 MAC merge layer configuration
> + * @verify_time: see struct ethtool_mm_state
> + * @verify_enabled: see struct ethtool_mm_state
> + * @tx_enabled: see struct ethtool_mm_state
> + * @pmac_enabled: see struct ethtool_mm_state
> + * @add_frag_size: see struct ethtool_mm_state */ struct
> +ethtool_mm_cfg {
> + u32 verify_time;
> + bool verify_enabled;
> + bool tx_enabled;
> + bool pmac_enabled;
> + u32 add_frag_size;
> +};
> +
> +/**
> + * struct ethtool_mm_stats - 802.3 MAC merge layer statistics
> + * @MACMergeFrameAssErrorCount:
> + * received MAC frames with reassembly errors
> + * @MACMergeFrameSmdErrorCount:
> + * received MAC frames/fragments rejected due to unknown or
> incorrect SMD
> + * @MACMergeFrameAssOkCount:
> + * received MAC frames that were successfully reassembled and passed
> up
> + * @MACMergeFragCountRx:
> + * number of additional correct SMD-C mPackets received due to
> preemption
> + * @MACMergeFragCountTx:
> + * number of additional mPackets sent due to preemption
> + * @MACMergeHoldCount:
> + * number of times the MM layer entered the HOLD state, which blocks
> + * transmission of preemptible traffic
> + */
> +struct ethtool_mm_stats {
> + u64 MACMergeFrameAssErrorCount;
> + u64 MACMergeFrameSmdErrorCount;
> + u64 MACMergeFrameAssOkCount;
> + u64 MACMergeFragCountRx;
> + u64 MACMergeFragCountTx;
> + u64 MACMergeHoldCount;
> +};
> +
> /**
> * struct ethtool_ops - optional netdev operations
> * @cap_link_lanes_supported: indicates if the driver supports lanes @@ -
> 639,6 +731,9 @@ struct ethtool_module_power_mode_params {
> * plugged-in.
> * @set_module_power_mode: Set the power mode policy for the plug-in
> module
> * used by the network device.
> + * @get_mm: Query the 802.3 MAC Merge layer state.
> + * @set_mm: Set the 802.3 MAC Merge layer parameters.
> + * @get_mm_stats: Query the 802.3 MAC Merge layer statistics.
> *
> * All operations are optional (i.e. the function pointer may be set
> * to %NULL) and callers must take this into account. Callers must @@ -
> 777,6 +872,10 @@ struct ethtool_ops {
> int (*set_module_power_mode)(struct net_device *dev,
> const struct
> ethtool_module_power_mode_params *params,
> struct netlink_ext_ack *extack);
> + void (*get_mm)(struct net_device *dev, struct ethtool_mm_state
> *state);
> + int (*set_mm)(struct net_device *dev, struct ethtool_mm_cfg
> *cfg,
> + struct netlink_ext_ack *extack);
> + void (*get_mm_stats)(struct net_device *dev, struct
> ethtool_mm_stats *stats);
> };
>

Does it make sense to have two separate functions, one to enable/disable pmac and tx preemption status and configure additional fragment size (both parameters can be configured after negotiating with the link partner), and another to modify the verification related parameters, i.e, enable/disable verification and verify time value?
For example, if the user wants to change the verify time value, Is there a way to change it without disturbing the value of the additional fragment size that has been set through LLDP after negotiating with the link partner?

> int ethtool_check_ops(const struct ethtool_ops *ops); diff --git
> a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h index
> 3135fa0ba9a4..7ddc47a3fb32 100644
> --- a/include/uapi/linux/ethtool.h
> +++ b/include/uapi/linux/ethtool.h
> @@ -779,6 +779,31 @@ enum ethtool_podl_pse_pw_d_status {
> ETHTOOL_PODL_PSE_PW_D_STATUS_ERROR,
> };
>
> +/**
> + * enum ethtool_mm_verify_status - status of MAC Merge Verify function
> + * @ETHTOOL_MM_VERIFY_STATUS_UNKNOWN:
> + * verification status is unknown
> + * @ETHTOOL_MM_VERIFY_STATUS_INITIAL:
> + * the 802.3 Verify State diagram is in the state INIT_VERIFICATION
> + * @ETHTOOL_MM_VERIFY_STATUS_VERIFYING:
> + * the Verify State diagram is in the state VERIFICATION_IDLE,
> + * SEND_VERIFY or WAIT_FOR_RESPONSE
> + * @ETHTOOL_MM_VERIFY_STATUS_SUCCEEDED:
> + * indicates that the Verify State diagram is in the state VERIFIED
> + * @ETHTOOL_MM_VERIFY_STATUS_FAILED:
> + * the Verify State diagram is in the state VERIFY_FAIL
> + * @ETHTOOL_MM_VERIFY_STATUS_DISABLED:
> + * verification of preemption operation is disabled
> + */
> +enum ethtool_mm_verify_status {
> + ETHTOOL_MM_VERIFY_STATUS_UNKNOWN,
> + ETHTOOL_MM_VERIFY_STATUS_INITIAL,
> + ETHTOOL_MM_VERIFY_STATUS_VERIFYING,
> + ETHTOOL_MM_VERIFY_STATUS_SUCCEEDED,
> + ETHTOOL_MM_VERIFY_STATUS_FAILED,
> + ETHTOOL_MM_VERIFY_STATUS_DISABLED,
> +};
> +
> /**
> * struct ethtool_gstrings - string set for data tagging
> * @cmd: Command number = %ETHTOOL_GSTRINGS diff --git
> a/include/uapi/linux/ethtool_netlink.h
> b/include/uapi/linux/ethtool_netlink.h
> index 5799a9db034e..e84a80957138 100644
> --- a/include/uapi/linux/ethtool_netlink.h
> +++ b/include/uapi/linux/ethtool_netlink.h
> @@ -52,6 +52,8 @@ enum {
> ETHTOOL_MSG_PSE_GET,
> ETHTOOL_MSG_PSE_SET,
> ETHTOOL_MSG_RSS_GET,
> + ETHTOOL_MSG_MM_GET,
> + ETHTOOL_MSG_MM_SET,
>
> /* add new constants above here */
> __ETHTOOL_MSG_USER_CNT,
> @@ -99,6 +101,8 @@ enum {
> ETHTOOL_MSG_MODULE_NTF,
> ETHTOOL_MSG_PSE_GET_REPLY,
> ETHTOOL_MSG_RSS_GET_REPLY,
> + ETHTOOL_MSG_MM_GET_REPLY,
> + ETHTOOL_MSG_MM_NTF,
>
> /* add new constants above here */
> __ETHTOOL_MSG_KERNEL_CNT,
> @@ -894,6 +898,49 @@ enum {
> ETHTOOL_A_RSS_MAX = (__ETHTOOL_A_RSS_CNT - 1), };
>
> +/* MAC Merge (802.3) */
> +
> +enum {
> + ETHTOOL_A_MM_STAT_UNSPEC,
> + ETHTOOL_A_MM_STAT_PAD,
> +
> + /* aMACMergeFrameAssErrorCount */
> + ETHTOOL_A_MM_STAT_REASSEMBLY_ERRORS, /* u64 */
> + /* aMACMergeFrameSmdErrorCount */
> + ETHTOOL_A_MM_STAT_SMD_ERRORS, /* u64 */
> + /* aMACMergeFrameAssOkCount */
> + ETHTOOL_A_MM_STAT_REASSEMBLY_OK, /* u64 */
> + /* aMACMergeFragCountRx */
> + ETHTOOL_A_MM_STAT_RX_FRAG_COUNT, /* u64 */
> + /* aMACMergeFragCountTx */
> + ETHTOOL_A_MM_STAT_TX_FRAG_COUNT, /* u64 */
> + /* aMACMergeHoldCount */
> + ETHTOOL_A_MM_STAT_HOLD_COUNT, /* u64 */
> +
> + /* add new constants above here */
> + __ETHTOOL_A_MM_STAT_CNT,
> + ETHTOOL_A_MM_STAT_MAX = (__ETHTOOL_A_MM_STAT_CNT - 1)
> };
> +
> +enum {
> + ETHTOOL_A_MM_UNSPEC,
> + ETHTOOL_A_MM_HEADER, /* nest -
> _A_HEADER_* */
> + ETHTOOL_A_MM_SUPPORTED, /* u8 */
> + ETHTOOL_A_MM_PMAC_ENABLED, /* u8 */
> + ETHTOOL_A_MM_TX_ENABLED, /* u8 */
> + ETHTOOL_A_MM_TX_ACTIVE, /* u8 */
> + ETHTOOL_A_MM_ADD_FRAG_SIZE, /* u32 */
> + ETHTOOL_A_MM_VERIFY_ENABLED, /* u8 */
> + ETHTOOL_A_MM_VERIFY_STATUS, /* u8 */
> + ETHTOOL_A_MM_VERIFY_TIME, /* u32 */
> + ETHTOOL_A_MM_MAX_VERIFY_TIME, /* u32 */
> + ETHTOOL_A_MM_STATS, /* nest -
> _A_MM_STAT_* */
> +
> + /* add new constants above here */
> + __ETHTOOL_A_MM_CNT,
> + ETHTOOL_A_MM_MAX = (__ETHTOOL_A_MM_CNT - 1) };
> +
> /* generic netlink info */
> #define ETHTOOL_GENL_NAME "ethtool"
> #define ETHTOOL_GENL_VERSION 1
> diff --git a/net/ethtool/Makefile b/net/ethtool/Makefile index
> 228f13df2e18..ab824b2d3b7d 100644
> --- a/net/ethtool/Makefile
> +++ b/net/ethtool/Makefile
> @@ -7,5 +7,5 @@ obj-$(CONFIG_ETHTOOL_NETLINK) += ethtool_nl.o
> ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o rss.o \
> linkstate.o debug.o wol.o features.o privflags.o rings.o \
> channels.o coalesce.o pause.o eee.o tsinfo.o cabletest.o \
> - tunnels.o fec.o eeprom.o stats.o phc_vclocks.o module.o \
> - pse-pd.o
> + tunnels.o fec.o eeprom.o stats.o phc_vclocks.o mm.o \
> + module.o pse-pd.o
> diff --git a/net/ethtool/mm.c b/net/ethtool/mm.c new file mode 100644
> index 000000000000..01a2acc40046
> --- /dev/null
> +++ b/net/ethtool/mm.c
> @@ -0,0 +1,258 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright 2022-2023 NXP
> + */
> +#include "common.h"
> +#include "netlink.h"
> +
> +struct mm_req_info {
> + struct ethnl_req_info base;
> +};
> +
> +struct mm_reply_data {
> + struct ethnl_reply_data base;
> + struct ethtool_mm_state state;
> + struct ethtool_mm_stats stats;
> +};
> +
> +#define MM_REPDATA(__reply_base) \
> + container_of(__reply_base, struct mm_reply_data, base)
> +
> +#define ETHTOOL_MM_STAT_CNT \
> + (__ETHTOOL_A_MM_STAT_CNT - (ETHTOOL_A_MM_STAT_PAD + 1))
> +
> +const struct nla_policy ethnl_mm_get_policy[ETHTOOL_A_MM_HEADER +
> 1] = {
> + [ETHTOOL_A_MM_HEADER] =
> NLA_POLICY_NESTED(ethnl_header_policy_stats),
> +};
> +
> +static int mm_prepare_data(const struct ethnl_req_info *req_base,
> + struct ethnl_reply_data *reply_base,
> + struct genl_info *info)
> +{
> + struct mm_reply_data *data = MM_REPDATA(reply_base);
> + struct net_device *dev = reply_base->dev;
> + const struct ethtool_ops *ops;
> + int ret;
> +
> + ops = dev->ethtool_ops;
> +
> + if (!ops->get_mm)
> + return -EOPNOTSUPP;
> +
> + ethtool_stats_init((u64 *)&data->stats,
> + sizeof(data->stats) / sizeof(u64));
> +
> + ret = ethnl_ops_begin(dev);
> + if (ret < 0)
> + return ret;
> +
> + ops->get_mm(dev, &data->state);
> +
> + if (ops->get_mm_stats && (req_base->flags &
> ETHTOOL_FLAG_STATS))
> + ops->get_mm_stats(dev, &data->stats);
> +
> + ethnl_ops_complete(dev);
> +
> + return 0;
> +}
> +
> +static int mm_reply_size(const struct ethnl_req_info *req_base,
> + const struct ethnl_reply_data *reply_base) {
> + struct mm_reply_data *data = MM_REPDATA(reply_base);
> + const struct ethtool_mm_state *state = &data->state;
> + int len = nla_total_size(sizeof(u8)); /* _MM_SUPPORTED */
> +
> + if (!state->supported)
> + return len;
> +
> + len += nla_total_size(sizeof(u8)); /* _MM_PMAC_ENABLED */
> + len += nla_total_size(sizeof(u8)); /* _MM_TX_ENABLED */
> + len += nla_total_size(sizeof(u8)); /* _MM_TX_ACTIVE */
> + len += nla_total_size(sizeof(u8)); /* _MM_VERIFY_ENABLED */
> + len += nla_total_size(sizeof(u8)); /* _MM_VERIFY_STATUS */
> + len += nla_total_size(sizeof(u32)); /* _MM_VERIFY_TIME */
> + len += nla_total_size(sizeof(u32)); /* _MM_MAX_VERIFY_TIME */
> + len += nla_total_size(sizeof(u32)); /* _MM_ADD_FRAG_SIZE */
> +
> + if (req_base->flags & ETHTOOL_FLAG_STATS)
> + len += nla_total_size(0) + /* _MM_STATS */
> + nla_total_size_64bit(sizeof(u64)) *
> ETHTOOL_MM_STAT_CNT;
> +
> + return len;
> +}
> +
> +static int mm_put_stat(struct sk_buff *skb, u64 val, u16 attrtype) {
> + if (val == ETHTOOL_STAT_NOT_SET)
> + return 0;
> + if (nla_put_u64_64bit(skb, attrtype, val,
> ETHTOOL_A_MM_STAT_PAD))
> + return -EMSGSIZE;
> + return 0;
> +}
> +
> +static int mm_put_stats(struct sk_buff *skb,
> + const struct ethtool_mm_stats *stats) {
> + struct nlattr *nest;
> +
> + nest = nla_nest_start(skb, ETHTOOL_A_MM_STATS);
> + if (!nest)
> + return -EMSGSIZE;
> +
> + if (mm_put_stat(skb, stats->MACMergeFrameAssErrorCount,
> + ETHTOOL_A_MM_STAT_REASSEMBLY_ERRORS) ||
> + mm_put_stat(skb, stats->MACMergeFrameSmdErrorCount,
> + ETHTOOL_A_MM_STAT_SMD_ERRORS) ||
> + mm_put_stat(skb, stats->MACMergeFrameAssOkCount,
> + ETHTOOL_A_MM_STAT_REASSEMBLY_OK) ||
> + mm_put_stat(skb, stats->MACMergeFragCountRx,
> + ETHTOOL_A_MM_STAT_RX_FRAG_COUNT) ||
> + mm_put_stat(skb, stats->MACMergeFragCountTx,
> + ETHTOOL_A_MM_STAT_TX_FRAG_COUNT) ||
> + mm_put_stat(skb, stats->MACMergeHoldCount,
> + ETHTOOL_A_MM_STAT_HOLD_COUNT))
> + goto err_cancel;
> +
> + nla_nest_end(skb, nest);
> + return 0;
> +
> +err_cancel:
> + nla_nest_cancel(skb, nest);
> + return -EMSGSIZE;
> +}
> +
> +static int mm_fill_reply(struct sk_buff *skb,
> + const struct ethnl_req_info *req_base,
> + const struct ethnl_reply_data *reply_base) {
> + const struct mm_reply_data *data = MM_REPDATA(reply_base);
> + const struct ethtool_mm_state *state = &data->state;
> +
> + if (nla_put_u8(skb, ETHTOOL_A_MM_SUPPORTED, state-
> >supported))
> + return -EMSGSIZE;
> +
> + if (!state->supported)
> + return 0;
> +
> + if (nla_put_u8(skb, ETHTOOL_A_MM_TX_ENABLED, state-
> >tx_enabled) ||
> + nla_put_u8(skb, ETHTOOL_A_MM_TX_ACTIVE, state->tx_active) ||
> + nla_put_u8(skb, ETHTOOL_A_MM_PMAC_ENABLED, state-
> >pmac_enabled) ||
> + nla_put_u8(skb, ETHTOOL_A_MM_VERIFY_ENABLED, state-
> >verify_enabled) ||
> + nla_put_u8(skb, ETHTOOL_A_MM_VERIFY_STATUS, state-
> >verify_status) ||
> + nla_put_u32(skb, ETHTOOL_A_MM_VERIFY_TIME, state-
> >verify_time) ||
> + nla_put_u32(skb, ETHTOOL_A_MM_MAX_VERIFY_TIME, state-
> >max_verify_time) ||
> + nla_put_u32(skb, ETHTOOL_A_MM_ADD_FRAG_SIZE, state-
> >add_frag_size))
> + return -EMSGSIZE;
> +
> + if (req_base->flags & ETHTOOL_FLAG_STATS &&
> + mm_put_stats(skb, &data->stats))
> + return -EMSGSIZE;
> +
> + return 0;
> +}
> +
> +const struct ethnl_request_ops ethnl_mm_request_ops = {
> + .request_cmd = ETHTOOL_MSG_MM_GET,
> + .reply_cmd = ETHTOOL_MSG_MM_GET_REPLY,
> + .hdr_attr = ETHTOOL_A_MM_HEADER,
> + .req_info_size = sizeof(struct mm_req_info),
> + .reply_data_size = sizeof(struct mm_reply_data),
> +
> + .prepare_data = mm_prepare_data,
> + .reply_size = mm_reply_size,
> + .fill_reply = mm_fill_reply,
> +};
> +
> +const struct nla_policy ethnl_mm_set_policy[ETHTOOL_A_MM_MAX + 1] = {
> + [ETHTOOL_A_MM_HEADER] =
> NLA_POLICY_NESTED(ethnl_header_policy),
> + [ETHTOOL_A_MM_VERIFY_ENABLED] = NLA_POLICY_MAX(NLA_U8,
> 1),
> + [ETHTOOL_A_MM_VERIFY_TIME] =
> NLA_POLICY_RANGE(NLA_U32, 1, 128),
> + [ETHTOOL_A_MM_TX_ENABLED] = NLA_POLICY_MAX(NLA_U8,
> 1),
> + [ETHTOOL_A_MM_PMAC_ENABLED] = NLA_POLICY_MAX(NLA_U8,
> 1),
> + [ETHTOOL_A_MM_ADD_FRAG_SIZE] =
> NLA_POLICY_RANGE(NLA_U32, 60, 252),
> +};
> +
> +static void mm_state_to_cfg(const struct ethtool_mm_state *state,
> + struct ethtool_mm_cfg *cfg)
> +{
> + /* We could also compare state->verify_status against
> + * ETHTOOL_MM_VERIFY_STATUS_DISABLED, but state-
> >verify_enabled
> + * is more like an administrative state which should be seen in
> + * ETHTOOL_MSG_MM_GET replies. For example, a port with
> verification
> + * disabled might be in the ETHTOOL_MM_VERIFY_STATUS_INITIAL
> + * if it's down.
> + */
> + cfg->verify_enabled = state->verify_enabled;
> + cfg->verify_time = state->verify_time;
> + cfg->tx_enabled = state->tx_enabled;
> + cfg->pmac_enabled = state->pmac_enabled;
> + cfg->add_frag_size = state->add_frag_size; }
> +
> +int ethnl_set_mm(struct sk_buff *skb, struct genl_info *info) {
> + struct netlink_ext_ack *extack = info->extack;
> + struct ethnl_req_info req_info = {};
> + struct ethtool_mm_state state = {};
> + struct nlattr **tb = info->attrs;
> + struct ethtool_mm_cfg cfg = {};
> + const struct ethtool_ops *ops;
> + struct net_device *dev;
> + bool mod = false;
> + int ret;
> +
> + ret = ethnl_parse_header_dev_get(&req_info,
> tb[ETHTOOL_A_MM_HEADER],
> + genl_info_net(info), extack, true);
> + if (ret)
> + return ret;
> +
> + dev = req_info.dev;
> + ops = dev->ethtool_ops;
> +
> + if (!ops->get_mm || !ops->set_mm) {
> + ret = -EOPNOTSUPP;
> + goto out_dev;
> + }
> +
> + rtnl_lock();
> + ret = ethnl_ops_begin(dev);
> + if (ret)
> + goto out_rtnl;
> +
> + ops->get_mm(dev, &state);
> +
> + mm_state_to_cfg(&state, &cfg);
> +
> + if (cfg.verify_time > state.max_verify_time) {
> + NL_SET_ERR_MSG_MOD(extack, "verifyTime exceeds device
> maximum");
> + return -ERANGE;
> + }
> +
> + ethnl_update_bool(&cfg.verify_enabled,
> tb[ETHTOOL_A_MM_VERIFY_ENABLED],
> + &mod);
> + ethnl_update_u32(&cfg.verify_time,
> tb[ETHTOOL_A_MM_VERIFY_TIME], &mod);
> + ethnl_update_bool(&cfg.tx_enabled,
> tb[ETHTOOL_A_MM_TX_ENABLED], &mod);
> + ethnl_update_bool(&cfg.pmac_enabled,
> tb[ETHTOOL_A_MM_PMAC_ENABLED],
> + &mod);
> + ethnl_update_u32(&cfg.add_frag_size,
> tb[ETHTOOL_A_MM_ADD_FRAG_SIZE],
> + &mod);
> +
> + ret = ops->set_mm(dev, &cfg, extack);
> + if (ret) {
> + if (!extack->_msg)
> + NL_SET_ERR_MSG(extack,
> + "Failed to update MAC merge
> configuration");
> + goto out_ops;
> + }
> +
> + ethtool_notify(dev, ETHTOOL_MSG_MM_NTF, NULL);
> +
> +out_ops:
> + ethnl_ops_complete(dev);
> +out_rtnl:
> + rtnl_unlock();
> +out_dev:
> + dev_put(dev);
> + return ret;
> +}
> diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c index
> aee98be6237f..a8c5b2521c46 100644
> --- a/net/ethtool/netlink.c
> +++ b/net/ethtool/netlink.c
> @@ -288,6 +288,7 @@
> ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
> [ETHTOOL_MSG_MODULE_GET] =
> &ethnl_module_request_ops,
> [ETHTOOL_MSG_PSE_GET] = &ethnl_pse_request_ops,
> [ETHTOOL_MSG_RSS_GET] = &ethnl_rss_request_ops,
> + [ETHTOOL_MSG_MM_GET] = &ethnl_mm_request_ops,
> };
>
> static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback
> *cb) @@ -603,6 +604,7 @@
> ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
> [ETHTOOL_MSG_EEE_NTF] = &ethnl_eee_request_ops,
> [ETHTOOL_MSG_FEC_NTF] = &ethnl_fec_request_ops,
> [ETHTOOL_MSG_MODULE_NTF] =
> &ethnl_module_request_ops,
> + [ETHTOOL_MSG_MM_NTF] = &ethnl_mm_request_ops,
> };
>
> /* default notification handler */
> @@ -696,6 +698,7 @@ static const ethnl_notify_handler_t
> ethnl_notify_handlers[] = {
> [ETHTOOL_MSG_EEE_NTF] = ethnl_default_notify,
> [ETHTOOL_MSG_FEC_NTF] = ethnl_default_notify,
> [ETHTOOL_MSG_MODULE_NTF] = ethnl_default_notify,
> + [ETHTOOL_MSG_MM_NTF] = ethnl_default_notify,
> };
>
> void ethtool_notify(struct net_device *dev, unsigned int cmd, const void
> *data) @@ -1047,6 +1050,22 @@ static const struct genl_ops
> ethtool_genl_ops[] = {
> .policy = ethnl_rss_get_policy,
> .maxattr = ARRAY_SIZE(ethnl_rss_get_policy) - 1,
> },
> + {
> + .cmd = ETHTOOL_MSG_MM_GET,
> + .doit = ethnl_default_doit,
> + .start = ethnl_default_start,
> + .dumpit = ethnl_default_dumpit,
> + .done = ethnl_default_done,
> + .policy = ethnl_mm_get_policy,
> + .maxattr = ARRAY_SIZE(ethnl_mm_get_policy) - 1,
> + },
> + {
> + .cmd = ETHTOOL_MSG_MM_SET,
> + .flags = GENL_UNS_ADMIN_PERM,
> + .doit = ethnl_set_mm,
> + .policy = ethnl_mm_set_policy,
> + .maxattr = ARRAY_SIZE(ethnl_mm_set_policy) - 1,
> + },
> };
>
> static const struct genl_multicast_group ethtool_nl_mcgrps[] = { diff --git
> a/net/ethtool/netlink.h b/net/ethtool/netlink.h index
> 744b3ab966b0..a8012dbe39bb 100644
> --- a/net/ethtool/netlink.h
> +++ b/net/ethtool/netlink.h
> @@ -373,6 +373,7 @@ extern const struct ethnl_request_ops
> ethnl_phc_vclocks_request_ops; extern const struct ethnl_request_ops
> ethnl_module_request_ops; extern const struct ethnl_request_ops
> ethnl_pse_request_ops; extern const struct ethnl_request_ops
> ethnl_rss_request_ops;
> +extern const struct ethnl_request_ops ethnl_mm_request_ops;
>
> extern const struct nla_policy
> ethnl_header_policy[ETHTOOL_A_HEADER_FLAGS + 1]; extern const struct
> nla_policy ethnl_header_policy_stats[ETHTOOL_A_HEADER_FLAGS + 1]; @@
> -414,6 +415,8 @@ extern const struct nla_policy
> ethnl_module_set_policy[ETHTOOL_A_MODULE_POWER_MO
> extern const struct nla_policy
> ethnl_pse_get_policy[ETHTOOL_A_PSE_HEADER + 1]; extern const struct
> nla_policy ethnl_pse_set_policy[ETHTOOL_A_PSE_MAX + 1]; extern const
> struct nla_policy ethnl_rss_get_policy[ETHTOOL_A_RSS_CONTEXT + 1];
> +extern const struct nla_policy
> ethnl_mm_get_policy[ETHTOOL_A_MM_HEADER
> ++ 1]; extern const struct nla_policy
> +ethnl_mm_set_policy[ETHTOOL_A_MM_MAX + 1];
>
> int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info); int
> ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info); @@ -434,6
> +437,7 @@ int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct
> netlink_callback *cb); int ethnl_set_fec(struct sk_buff *skb, struct genl_info
> *info); int ethnl_set_module(struct sk_buff *skb, struct genl_info *info); int
> ethnl_set_pse(struct sk_buff *skb, struct genl_info *info);
> +int ethnl_set_mm(struct sk_buff *skb, struct genl_info *info);
>
> extern const char
> stats_std_names[__ETHTOOL_STATS_CNT][ETH_GSTRING_LEN];
> extern const char
> stats_eth_phy_names[__ETHTOOL_A_STATS_ETH_PHY_CNT][ETH_GSTRING_
> LEN];
> --
> 2.34.1