[PATCH net-next v9 11/14] ethtool: provide link mode information with LINKMODES_GET request

From: Michal Kubecek
Date: Fri Dec 27 2019 - 09:56:15 EST

Implement LINKMODES_GET netlink request to get link modes related
information provided by ETHTOOL_GLINKSETTINGS and ETHTOOL_GSET ioctl
commands.

This request provides supported, advertised and peer advertised link modes,
autonegotiation flag, speed and duplex.

LINKMODES_GET request can be used with NLM_F_DUMP (without device
identification) to request the information for all devices in current
network namespace providing the data.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
Documentation/networking/ethtool-netlink.rst | 36 +++++
include/linux/ethtool_netlink.h | 3 +
include/uapi/linux/ethtool_netlink.h | 18 +++
net/ethtool/Makefile | 2 +-
net/ethtool/linkmodes.c | 140 +++++++++++++++++++
net/ethtool/netlink.c | 8 ++
net/ethtool/netlink.h | 1 +
7 files changed, 207 insertions(+), 1 deletion(-)
create mode 100644 net/ethtool/linkmodes.c

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 34254482d295..04c55be0264c 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -182,6 +182,7 @@ Userspace to kernel:
``ETHTOOL_MSG_STRSET_GET`` get string set
``ETHTOOL_MSG_LINKINFO_GET`` get link settings
``ETHTOOL_MSG_LINKINFO_SET`` set link settings
+ ``ETHTOOL_MSG_LINKMODES_GET`` get link modes info
===================================== ================================

Kernel to userspace:
@@ -190,6 +191,7 @@ Kernel to userspace:
``ETHTOOL_MSG_STRSET_GET_REPLY`` string set contents
``ETHTOOL_MSG_LINKINFO_GET_REPLY`` link settings
``ETHTOOL_MSG_LINKINFO_NTF`` link settings notification
+ ``ETHTOOL_MSG_LINKMODES_GET_REPLY`` link modes info
===================================== ================================

``GET`` requests are sent by userspace applications to retrieve device
@@ -332,6 +334,38 @@ MDI(-X) status and transceiver cannot be set, request with the corresponding
attributes is rejected.


+LINKMODES_GET
+=============
+
+Requests link modes (supported, advertised and peer advertised) and related
+information (autonegotiation status, link speed and duplex) as provided by
+``ETHTOOL_GLINKSETTINGS``. The request does not use any attributes.
+
+Request contents:
+
+ ==================================== ====== ==========================
+ ``ETHTOOL_A_LINKMODES_HEADER`` nested request header
+ ==================================== ====== ==========================
+
+Kernel response contents:
+
+ ==================================== ====== ==========================
+ ``ETHTOOL_A_LINKMODES_HEADER`` nested reply header
+ ``ETHTOOL_A_LINKMODES_AUTONEG`` u8 autonegotiation status
+ ``ETHTOOL_A_LINKMODES_OURS`` bitset advertised link modes
+ ``ETHTOOL_A_LINKMODES_PEER`` bitset partner link modes
+ ``ETHTOOL_A_LINKMODES_SPEED`` u32 link speed (Mb/s)
+ ``ETHTOOL_A_LINKMODES_DUPLEX`` u8 duplex mode
+ ==================================== ====== ==========================
+
+For ``ETHTOOL_A_LINKMODES_OURS``, value represents advertised modes and mask
+represents supported modes. ``ETHTOOL_A_LINKMODES_PEER`` in the reply is a bit
+list.
+
+``LINKMODES_GET`` allows dump requests (kernel returns reply messages for all
+devices supporting the request).
+
+
Request translation
===================

@@ -343,6 +377,7 @@ have their netlink replacement yet.
ioctl command netlink command
=================================== =====================================
``ETHTOOL_GSET`` ``ETHTOOL_MSG_LINKINFO_GET``
+ ``ETHTOOL_MSG_LINKMODES_GET``
``ETHTOOL_SSET`` ``ETHTOOL_MSG_LINKINFO_SET``
``ETHTOOL_GDRVINFO`` n/a
``ETHTOOL_GREGS`` n/a
@@ -417,6 +452,7 @@ have their netlink replacement yet.
``ETHTOOL_GPHYSTATS`` n/a
``ETHTOOL_PERQUEUE`` n/a
``ETHTOOL_GLINKSETTINGS`` ``ETHTOOL_MSG_LINKINFO_GET``
+ ``ETHTOOL_MSG_LINKMODES_GET``
``ETHTOOL_SLINKSETTINGS`` ``ETHTOOL_MSG_LINKINFO_SET``
``ETHTOOL_PHY_GTUNABLE`` n/a
``ETHTOOL_PHY_STUNABLE`` n/a
diff --git a/include/linux/ethtool_netlink.h b/include/linux/ethtool_netlink.h
index c98f6852c8eb..d01b77887f82 100644
--- a/include/linux/ethtool_netlink.h
+++ b/include/linux/ethtool_netlink.h
@@ -7,6 +7,9 @@
#include <linux/ethtool.h>
#include <linux/netdevice.h>

+#define __ETHTOOL_LINK_MODE_MASK_NWORDS \
+ DIV_ROUND_UP(__ETHTOOL_LINK_MODE_MASK_NBITS, 32)
+
enum ethtool_multicast_groups {
ETHNL_MCGRP_MONITOR,
};
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index d530fa30de36..dc1cae052eee 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -17,6 +17,7 @@ enum {
ETHTOOL_MSG_STRSET_GET,
ETHTOOL_MSG_LINKINFO_GET,
ETHTOOL_MSG_LINKINFO_SET,
+ ETHTOOL_MSG_LINKMODES_GET,

/* add new constants above here */
__ETHTOOL_MSG_USER_CNT,
@@ -29,6 +30,7 @@ enum {
ETHTOOL_MSG_STRSET_GET_REPLY,
ETHTOOL_MSG_LINKINFO_GET_REPLY,
ETHTOOL_MSG_LINKINFO_NTF,
+ ETHTOOL_MSG_LINKMODES_GET_REPLY,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
@@ -161,6 +163,22 @@ enum {
ETHTOOL_A_LINKINFO_MAX = __ETHTOOL_A_LINKINFO_CNT - 1
};

+/* LINKMODES */
+
+enum {
+ ETHTOOL_A_LINKMODES_UNSPEC,
+ ETHTOOL_A_LINKMODES_HEADER, /* nest - _A_HEADER_* */
+ ETHTOOL_A_LINKMODES_AUTONEG, /* u8 */
+ ETHTOOL_A_LINKMODES_OURS, /* bitset */
+ ETHTOOL_A_LINKMODES_PEER, /* bitset */
+ ETHTOOL_A_LINKMODES_SPEED, /* u32 */
+ ETHTOOL_A_LINKMODES_DUPLEX, /* u8 */
+
+ /* add new constants above here */
+ __ETHTOOL_A_LINKMODES_CNT,
+ ETHTOOL_A_LINKMODES_MAX = __ETHTOOL_A_LINKMODES_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 765736ec52c0..8023da6672ce 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -4,4 +4,4 @@ obj-y += ioctl.o common.o

obj-$(CONFIG_ETHTOOL_NETLINK) += ethtool_nl.o

-ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o
+ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o
diff --git a/net/ethtool/linkmodes.c b/net/ethtool/linkmodes.c
new file mode 100644
index 000000000000..81856fa1e632
--- /dev/null
+++ b/net/ethtool/linkmodes.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+#include "bitset.h"
+
+struct linkmodes_req_info {
+ struct ethnl_req_info base;
+};
+
+struct linkmodes_reply_data {
+ struct ethnl_reply_data base;
+ struct ethtool_link_ksettings ksettings;
+ struct ethtool_link_settings *lsettings;
+ bool peer_empty;
+};
+
+#define LINKMODES_REPDATA(__reply_base) \
+ container_of(__reply_base, struct linkmodes_reply_data, base)
+
+static const struct nla_policy
+linkmodes_get_policy[ETHTOOL_A_LINKMODES_MAX + 1] = {
+ [ETHTOOL_A_LINKMODES_UNSPEC] = { .type = NLA_REJECT },
+ [ETHTOOL_A_LINKMODES_HEADER] = { .type = NLA_NESTED },
+ [ETHTOOL_A_LINKMODES_AUTONEG] = { .type = NLA_REJECT },
+ [ETHTOOL_A_LINKMODES_OURS] = { .type = NLA_REJECT },
+ [ETHTOOL_A_LINKMODES_PEER] = { .type = NLA_REJECT },
+ [ETHTOOL_A_LINKMODES_SPEED] = { .type = NLA_REJECT },
+ [ETHTOOL_A_LINKMODES_DUPLEX] = { .type = NLA_REJECT },
+};
+
+static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ int ret;
+
+ data->lsettings = &data->ksettings.base;
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = __ethtool_get_link_ksettings(dev, &data->ksettings);
+ if (ret < 0 && info) {
+ GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
+ goto out;
+ }
+
+ data->peer_empty =
+ bitmap_empty(data->ksettings.link_modes.lp_advertising,
+ __ETHTOOL_LINK_MODE_MASK_NBITS);
+
+out:
+ ethnl_ops_complete(dev);
+ return ret;
+}
+
+static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
+ const struct ethtool_link_ksettings *ksettings = &data->ksettings;
+ bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+ int len, ret;
+
+ len = nla_total_size(sizeof(u8)) /* LINKMODES_AUTONEG */
+ + nla_total_size(sizeof(u32)) /* LINKMODES_SPEED */
+ + nla_total_size(sizeof(u8)) /* LINKMODES_DUPLEX */
+ + 0;
+ ret = ethnl_bitset_size(ksettings->link_modes.advertising,
+ ksettings->link_modes.supported,
+ __ETHTOOL_LINK_MODE_MASK_NBITS,
+ link_mode_names, compact);
+ if (ret < 0)
+ return ret;
+ len += ret;
+ if (!data->peer_empty) {
+ ret = ethnl_bitset_size(ksettings->link_modes.lp_advertising,
+ NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
+ link_mode_names, compact);
+ if (ret < 0)
+ return ret;
+ len += ret;
+ }
+
+ return len;
+}
+
+static int linkmodes_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
+ const struct ethtool_link_ksettings *ksettings = &data->ksettings;
+ const struct ethtool_link_settings *lsettings = &ksettings->base;
+ bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+ int ret;
+
+ if (nla_put_u8(skb, ETHTOOL_A_LINKMODES_AUTONEG, lsettings->autoneg))
+ return -EMSGSIZE;
+
+ ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_OURS,
+ ksettings->link_modes.advertising,
+ ksettings->link_modes.supported,
+ __ETHTOOL_LINK_MODE_MASK_NBITS, link_mode_names,
+ compact);
+ if (ret < 0)
+ return -EMSGSIZE;
+ if (!data->peer_empty) {
+ ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_PEER,
+ ksettings->link_modes.lp_advertising,
+ NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
+ link_mode_names, compact);
+ if (ret < 0)
+ return -EMSGSIZE;
+ }
+
+ if (nla_put_u32(skb, ETHTOOL_A_LINKMODES_SPEED, lsettings->speed) ||
+ nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+const struct ethnl_request_ops ethnl_linkmodes_request_ops = {
+ .request_cmd = ETHTOOL_MSG_LINKMODES_GET,
+ .reply_cmd = ETHTOOL_MSG_LINKMODES_GET_REPLY,
+ .hdr_attr = ETHTOOL_A_LINKMODES_HEADER,
+ .max_attr = ETHTOOL_A_LINKMODES_MAX,
+ .req_info_size = sizeof(struct linkmodes_req_info),
+ .reply_data_size = sizeof(struct linkmodes_reply_data),
+ .request_policy = linkmodes_get_policy,
+
+ .prepare_data = linkmodes_prepare_data,
+ .reply_size = linkmodes_reply_size,
+ .fill_reply = linkmodes_fill_reply,
+};
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 942da4ebdfe9..703ff3a227a4 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -209,6 +209,7 @@ static const struct ethnl_request_ops *
ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
[ETHTOOL_MSG_STRSET_GET] = &ethnl_strset_request_ops,
[ETHTOOL_MSG_LINKINFO_GET] = &ethnl_linkinfo_request_ops,
+ [ETHTOOL_MSG_LINKMODES_GET] = &ethnl_linkmodes_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -630,6 +631,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
.flags = GENL_UNS_ADMIN_PERM,
.doit = ethnl_set_linkinfo,
},
+ {
+ .cmd = ETHTOOL_MSG_LINKMODES_GET,
+ .doit = ethnl_default_doit,
+ .start = ethnl_default_start,
+ .dumpit = ethnl_default_dumpit,
+ .done = ethnl_default_done,
+ },
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 5d56d7779a06..256d38972d1e 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -332,6 +332,7 @@ struct ethnl_request_ops {

extern const struct ethnl_request_ops ethnl_strset_request_ops;
extern const struct ethnl_request_ops ethnl_linkinfo_request_ops;
+extern const struct ethnl_request_ops ethnl_linkmodes_request_ops;

int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);

--
2.24.1