[RFC PATCH net-next 6/7] net: ethtool: add a netlink command to get PHY information

From: Maxime Chevallier
Date: Thu Sep 07 2023 - 11:33:15 EST

Now that we can list PHYs belonging to a netdevice, add a command to get
PHY-specific information, that we can extend as needed to get more data
such as link info, offloading support, etc.

Signed-off-by: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>
---
include/uapi/linux/ethtool.h | 7 ++
include/uapi/linux/ethtool_netlink.h | 14 +++
net/ethtool/Makefile | 2 +-
net/ethtool/netlink.c | 10 +++
net/ethtool/netlink.h | 2 +
net/ethtool/phy.c | 124 +++++++++++++++++++++++++++
6 files changed, 158 insertions(+), 1 deletion(-)
create mode 100644 net/ethtool/phy.c

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index f7fba0dc87e5..d74f839ad32c 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -2205,4 +2205,11 @@ struct ethtool_link_settings {
* __u32 map_lp_advertising[link_mode_masks_nwords];
*/
};
+
+enum phy_upstream_type {
+ PHY_UPSTREAM_MAC,
+ PHY_UPSTREAM_SFP,
+ PHY_UPSTREAM_PHY,
+};
+
#endif /* _UAPI_LINUX_ETHTOOL_H */
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index b2a0d21fdd8e..ec96e816d564 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -58,6 +58,7 @@ enum {
ETHTOOL_MSG_MM_GET,
ETHTOOL_MSG_MM_SET,
ETHTOOL_MSG_PHY_LIST_GET,
+ ETHTOOL_MSG_PHY_GET,

/* add new constants above here */
__ETHTOOL_MSG_USER_CNT,
@@ -111,6 +112,7 @@ enum {
ETHTOOL_MSG_MM_GET_REPLY,
ETHTOOL_MSG_MM_NTF,
ETHTOOL_MSG_PHY_LIST_GET_REPLY,
+ ETHTOOL_MSG_PHY_GET_REPLY,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
@@ -988,6 +990,18 @@ enum {
ETHTOOL_A_PHY_LIST_MAX = (__ETHTOOL_A_PHY_LIST_CNT - 1)
};

+enum {
+ ETHTOOL_A_PHY_UNSPEC,
+ ETHTOOL_A_PHY_HEADER, /* nest - _A_HEADER_* */
+ ETHTOOL_A_PHY_INDEX, /* u32 */
+ ETHTOOL_A_PHY_DRVNAME, /* string */
+ ETHTOOL_A_PHY_UPSTREAM_TYPE, /* u8 */
+ ETHTOOL_A_PHY_ID, /* u32 */
+
+ __ETHTOOL_A_PHY_CNT,
+ ETHTOOL_A_PHY_MAX = (__ETHTOOL_A_PHY_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 a182c0dbbb9d..e6ef280431d6 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -8,4 +8,4 @@ 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 mm.o \
- module.o pse-pd.o plca.o mm.o phy_list.o
+ module.o pse-pd.o plca.o mm.o phy_list.o phy.o
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 60b66b78055e..88a60fbb8806 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -307,6 +307,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
[ETHTOOL_MSG_MM_GET] = &ethnl_mm_request_ops,
[ETHTOOL_MSG_MM_SET] = &ethnl_mm_request_ops,
[ETHTOOL_MSG_PHY_LIST_GET] = &ethnl_phy_list_request_ops,
+ [ETHTOOL_MSG_PHY_GET] = &ethnl_phy_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -1138,6 +1139,15 @@ static const struct genl_ops ethtool_genl_ops[] = {
.policy = ethnl_phy_list_get_policy,
.maxattr = ARRAY_SIZE(ethnl_phy_list_get_policy) - 1,
},
+ {
+ .cmd = ETHTOOL_MSG_PHY_GET,
+ .doit = ethnl_default_doit,
+ .start = ethnl_default_start,
+ .dumpit = ethnl_default_dumpit,
+ .done = ethnl_default_done,
+ .policy = ethnl_phy_get_policy,
+ .maxattr = ARRAY_SIZE(ethnl_phy_get_policy) - 1,
+ },
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 76859d8fbce0..15f75fd211fc 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -396,6 +396,7 @@ extern const struct ethnl_request_ops ethnl_plca_cfg_request_ops;
extern const struct ethnl_request_ops ethnl_plca_status_request_ops;
extern const struct ethnl_request_ops ethnl_mm_request_ops;
extern const struct ethnl_request_ops ethnl_phy_list_request_ops;
+extern const struct ethnl_request_ops ethnl_phy_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];
@@ -443,6 +444,7 @@ extern const struct nla_policy ethnl_plca_get_status_policy[ETHTOOL_A_PLCA_HEADE
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];
extern const struct nla_policy ethnl_phy_list_get_policy[ETHTOOL_A_PHY_LIST_HEADER + 1];
+extern const struct nla_policy ethnl_phy_get_policy[ETHTOOL_A_PHY_INDEX + 1];

int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info);
diff --git a/net/ethtool/phy.c b/net/ethtool/phy.c
new file mode 100644
index 000000000000..0f646bec946b
--- /dev/null
+++ b/net/ethtool/phy.c
@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2023 Bootlin
+ *
+ */
+#include "common.h"
+#include "netlink.h"
+
+#include <linux/phy.h>
+#include <linux/phy_ns.h>
+
+struct phy_req_info {
+ struct ethnl_req_info base;
+ u32 phyindex;
+};
+
+struct phy_reply_data {
+ struct ethnl_reply_data base;
+ u32 phyindex;
+ const char *drvname;
+ enum phy_upstream_type upstream;
+ u32 id;
+};
+
+#define PHY_REQINFO(__req_base) \
+ container_of(__req_base, struct phy_req_info, base)
+#define PHY_REPDATA(__reply_base) \
+ container_of(__reply_base, struct phy_reply_data, base)
+
+const struct nla_policy ethnl_phy_get_policy[ETHTOOL_A_PHY_INDEX + 1] = {
+ [ETHTOOL_A_PHY_HEADER] = NLA_POLICY_NESTED(ethnl_header_policy),
+ [ETHTOOL_A_PHY_INDEX] = NLA_POLICY_MAX(NLA_U32, 255),
+};
+
+static int phy_parse_request(struct ethnl_req_info *req_base,
+ struct nlattr **tb,
+ struct netlink_ext_ack *extack)
+{
+ struct phy_req_info *req_info = PHY_REQINFO(req_base);
+
+ if (!tb[ETHTOOL_A_PHY_INDEX])
+ return -EINVAL;
+
+ req_info->phyindex = nla_get_u32(tb[ETHTOOL_A_PHY_INDEX]);
+
+ return 0;
+}
+
+static int phy_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct phy_req_info *req_info = PHY_REQINFO(req_base);
+ struct phy_reply_data *data = PHY_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ struct phy_namespace *phy_ns = &dev->phy_ns;
+ struct phy_device *phydev;
+ int ret;
+
+ phydev = phy_ns_get_by_index(phy_ns, req_info->phyindex);
+ if (!phydev)
+ return -ENODEV;
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ return ret;
+
+ data->phyindex = req_info->phyindex;
+ data->drvname = phydev->drv->name;
+ if (phydev->is_on_sfp_module)
+ data->upstream = PHY_UPSTREAM_SFP;
+ else if (phydev->attached_dev)
+ data->upstream = PHY_UPSTREAM_MAC;
+ else
+ data->upstream = PHY_UPSTREAM_PHY;
+
+ data->id = phydev->phy_id;
+
+ ethnl_ops_complete(dev);
+
+ return ret;
+}
+
+static int phy_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct phy_reply_data *data = PHY_REPDATA(reply_base);
+ int len = 0;
+
+ len += nla_total_size(sizeof(u32)); /* ETHTOOL_A_PHY_INDEX */
+ len += ethnl_strz_size(data->drvname); /* ETHTOOL_A_DRVNAME */
+ len += nla_total_size(sizeof(u8)); /* ETHTOOL_A_PHY_UPSTREAM_TYPE */
+ len += nla_total_size(sizeof(u32)); /* ETHTOOL_A_PHY_ID */
+
+ return len;
+}
+
+static int phy_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct phy_reply_data *data = PHY_REPDATA(reply_base);
+
+ if (nla_put_u32(skb, ETHTOOL_A_PHY_INDEX, data->phyindex) ||
+ ethnl_put_strz(skb, ETHTOOL_A_PHY_DRVNAME, data->drvname) ||
+ nla_put_u8(skb, ETHTOOL_A_PHY_UPSTREAM_TYPE, data->upstream) ||
+ nla_put_u32(skb, ETHTOOL_A_PHY_ID, data->id))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+const struct ethnl_request_ops ethnl_phy_request_ops = {
+ .request_cmd = ETHTOOL_MSG_PHY_GET,
+ .reply_cmd = ETHTOOL_MSG_PHY_GET_REPLY,
+ .hdr_attr = ETHTOOL_A_PHY_HEADER,
+ .req_info_size = sizeof(struct phy_req_info),
+ .reply_data_size = sizeof(struct phy_reply_data),
+
+ .parse_request = phy_parse_request,
+ .prepare_data = phy_prepare_data,
+ .reply_size = phy_reply_size,
+ .fill_reply = phy_fill_reply,
+};
--
2.41.0