ethtool: provide EEE settings with EEE_GET request

Implement EEE_GET request to get EEE settings of a network device. These
are traditionally available via ETHTOOL_GEEE ioctl request.

The netlink interface allows reporting EEE status for all link modes
supported by kernel but only first 32 link modes are provided at the moment
as only those are reported by the ethtool_ops callback and drivers.

v2: fix alignment (whitespace only)

Signed-off-by: Michal Kubecek <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/networking/ethtool-netlink.rst

···
   ``ETHTOOL_MSG_COALESCE_SET``          set coalescing parameters
   ``ETHTOOL_MSG_PAUSE_GET``             get pause parameters
   ``ETHTOOL_MSG_PAUSE_SET``             set pause parameters
+  ``ETHTOOL_MSG_EEE_GET``               get EEE settings
   ===================================== ================================
 
 Kernel to userspace:
···
   ``ETHTOOL_MSG_COALESCE_NTF``          coalescing parameters
   ``ETHTOOL_MSG_PAUSE_GET_REPLY``       pause parameters
   ``ETHTOOL_MSG_PAUSE_NTF``             pause parameters
+  ``ETHTOOL_MSG_EEE_GET_REPLY``         EEE settings
   ===================================== =================================
 
 ``GET`` requests are sent by userspace applications to retrieve device
···
   =====================================  ======  ==========================
 
 
+EEE_GET
+=======
+
+Gets channel counts like ``ETHTOOL_GEEE`` ioctl request.
+
+Request contents:
+
+  =====================================  ======  ==========================
+  ``ETHTOOL_A_EEE_HEADER``               nested  request header
+  =====================================  ======  ==========================
+
+Kernel response contents:
+
+  =====================================  ======  ==========================
+  ``ETHTOOL_A_EEE_HEADER``               nested  request header
+  ``ETHTOOL_A_EEE_MODES_OURS``           bool    supported/advertised modes
+  ``ETHTOOL_A_EEE_MODES_PEER``           bool    peer advertised link modes
+  ``ETHTOOL_A_EEE_ACTIVE``               bool    EEE is actively used
+  ``ETHTOOL_A_EEE_ENABLED``              bool    EEE is enabled
+  ``ETHTOOL_A_EEE_TX_LPI_ENABLED``       bool    Tx lpi enabled
+  ``ETHTOOL_A_EEE_TX_LPI_TIMER``         u32     Tx lpi timeout (in us)
+  =====================================  ======  ==========================
+
+In ``ETHTOOL_A_EEE_MODES_OURS``, mask consists of link modes for which EEE is
+enabled, value of link modes for which EEE is advertised. Link modes for which
+peer advertises EEE are listed in ``ETHTOOL_A_EEE_MODES_PEER`` (no mask). The
+netlink interface allows reporting EEE status for all link modes but only
+first 32 are provided by the ``ethtool_ops`` callback.
+
+
 Request translation
 ===================
 
···
   ``ETHTOOL_GET_TS_INFO``             n/a
   ``ETHTOOL_GMODULEINFO``             n/a
   ``ETHTOOL_GMODULEEEPROM``           n/a
-  ``ETHTOOL_GEEE``                    n/a
+  ``ETHTOOL_GEEE``                    ``ETHTOOL_MSG_EEE_GET``
   ``ETHTOOL_SEEE``                    n/a
   ``ETHTOOL_GRSSH``                   n/a
   ``ETHTOOL_SRSSH``                   n/a

include/uapi/linux/ethtool_netlink.h

···
 	ETHTOOL_MSG_COALESCE_SET,
 	ETHTOOL_MSG_PAUSE_GET,
 	ETHTOOL_MSG_PAUSE_SET,
+	ETHTOOL_MSG_EEE_GET,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_USER_CNT,
···
 	ETHTOOL_MSG_COALESCE_NTF,
 	ETHTOOL_MSG_PAUSE_GET_REPLY,
 	ETHTOOL_MSG_PAUSE_NTF,
+	ETHTOOL_MSG_EEE_GET_REPLY,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_KERNEL_CNT,
···
 	/* add new constants above here */
 	__ETHTOOL_A_PAUSE_CNT,
 	ETHTOOL_A_PAUSE_MAX = (__ETHTOOL_A_PAUSE_CNT - 1)
+};
+
+/* EEE */
+
+enum {
+	ETHTOOL_A_EEE_UNSPEC,
+	ETHTOOL_A_EEE_HEADER,				/* nest - _A_HEADER_* */
+	ETHTOOL_A_EEE_MODES_OURS,			/* bitset */
+	ETHTOOL_A_EEE_MODES_PEER,			/* bitset */
+	ETHTOOL_A_EEE_ACTIVE,				/* u8 */
+	ETHTOOL_A_EEE_ENABLED,				/* u8 */
+	ETHTOOL_A_EEE_TX_LPI_ENABLED,			/* u8 */
+	ETHTOOL_A_EEE_TX_LPI_TIMER,			/* u32 */
+
+	/* add new constants above here */
+	__ETHTOOL_A_EEE_CNT,
+	ETHTOOL_A_EEE_MAX = (__ETHTOOL_A_EEE_CNT - 1)
 };
 
 /* generic netlink info */

net/ethtool/Makefile

···
 
 ethtool_nl-y	:= netlink.o bitset.o strset.o linkinfo.o linkmodes.o \
 		   linkstate.o debug.o wol.o features.o privflags.o rings.o \
-		   channels.o coalesce.o pause.o
+		   channels.o coalesce.o pause.o eee.o

net/ethtool/eee.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+#include "bitset.h"
+
+#define EEE_MODES_COUNT \
+	(sizeof_field(struct ethtool_eee, supported) * BITS_PER_BYTE)
+
+struct eee_req_info {
+	struct ethnl_req_info		base;
+};
+
+struct eee_reply_data {
+	struct ethnl_reply_data		base;
+	struct ethtool_eee		eee;
+};
+
+#define EEE_REPDATA(__reply_base) \
+	container_of(__reply_base, struct eee_reply_data, base)
+
+static const struct nla_policy
+eee_get_policy[ETHTOOL_A_EEE_MAX + 1] = {
+	[ETHTOOL_A_EEE_UNSPEC]		= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_HEADER]		= { .type = NLA_NESTED },
+	[ETHTOOL_A_EEE_MODES_OURS]	= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_MODES_PEER]	= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_ACTIVE]		= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_ENABLED]		= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_TX_LPI_ENABLED]	= { .type = NLA_REJECT },
+	[ETHTOOL_A_EEE_TX_LPI_TIMER]	= { .type = NLA_REJECT },
+};
+
+static int eee_prepare_data(const struct ethnl_req_info *req_base,
+			    struct ethnl_reply_data *reply_base,
+			    struct genl_info *info)
+{
+	struct eee_reply_data *data = EEE_REPDATA(reply_base);
+	struct net_device *dev = reply_base->dev;
+	int ret;
+
+	if (!dev->ethtool_ops->get_eee)
+		return -EOPNOTSUPP;
+	ret = ethnl_ops_begin(dev);
+	if (ret < 0)
+		return ret;
+	ret = dev->ethtool_ops->get_eee(dev, &data->eee);
+	ethnl_ops_complete(dev);
+
+	return ret;
+}
+
+static int eee_reply_size(const struct ethnl_req_info *req_base,
+			  const struct ethnl_reply_data *reply_base)
+{
+	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+	const struct eee_reply_data *data = EEE_REPDATA(reply_base);
+	const struct ethtool_eee *eee = &data->eee;
+	int len = 0;
+	int ret;
+
+	BUILD_BUG_ON(sizeof(eee->advertised) * BITS_PER_BYTE !=
+		     EEE_MODES_COUNT);
+	BUILD_BUG_ON(sizeof(eee->lp_advertised) * BITS_PER_BYTE !=
+		     EEE_MODES_COUNT);
+
+	/* MODES_OURS */
+	ret = ethnl_bitset32_size(&eee->advertised, &eee->supported,
+				  EEE_MODES_COUNT, link_mode_names, compact);
+	if (ret < 0)
+		return ret;
+	len += ret;
+	/* MODES_PEERS */
+	ret = ethnl_bitset32_size(&eee->lp_advertised, NULL,
+				  EEE_MODES_COUNT, link_mode_names, compact);
+	if (ret < 0)
+		return ret;
+	len += ret;
+
+	len += nla_total_size(sizeof(u8)) +	/* _EEE_ACTIVE */
+	       nla_total_size(sizeof(u8)) +	/* _EEE_ENABLED */
+	       nla_total_size(sizeof(u8)) +	/* _EEE_TX_LPI_ENABLED */
+	       nla_total_size(sizeof(u32));	/* _EEE_TX_LPI_TIMER */
+
+	return len;
+}
+
+static int eee_fill_reply(struct sk_buff *skb,
+			  const struct ethnl_req_info *req_base,
+			  const struct ethnl_reply_data *reply_base)
+{
+	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+	const struct eee_reply_data *data = EEE_REPDATA(reply_base);
+	const struct ethtool_eee *eee = &data->eee;
+	int ret;
+
+	ret = ethnl_put_bitset32(skb, ETHTOOL_A_EEE_MODES_OURS,
+				 &eee->advertised, &eee->supported,
+				 EEE_MODES_COUNT, link_mode_names, compact);
+	if (ret < 0)
+		return ret;
+	ret = ethnl_put_bitset32(skb, ETHTOOL_A_EEE_MODES_PEER,
+				 &eee->lp_advertised, NULL, EEE_MODES_COUNT,
+				 link_mode_names, compact);
+	if (ret < 0)
+		return ret;
+
+	if (nla_put_u8(skb, ETHTOOL_A_EEE_ACTIVE, !!eee->eee_active) ||
+	    nla_put_u8(skb, ETHTOOL_A_EEE_ENABLED, !!eee->eee_enabled) ||
+	    nla_put_u8(skb, ETHTOOL_A_EEE_TX_LPI_ENABLED,
+		       !!eee->tx_lpi_enabled) ||
+	    nla_put_u32(skb, ETHTOOL_A_EEE_TX_LPI_TIMER, eee->tx_lpi_timer))
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+const struct ethnl_request_ops ethnl_eee_request_ops = {
+	.request_cmd		= ETHTOOL_MSG_EEE_GET,
+	.reply_cmd		= ETHTOOL_MSG_EEE_GET_REPLY,
+	.hdr_attr		= ETHTOOL_A_EEE_HEADER,
+	.max_attr		= ETHTOOL_A_EEE_MAX,
+	.req_info_size		= sizeof(struct eee_req_info),
+	.reply_data_size	= sizeof(struct eee_reply_data),
+	.request_policy		= eee_get_policy,
+
+	.prepare_data		= eee_prepare_data,
+	.reply_size		= eee_reply_size,
+	.fill_reply		= eee_fill_reply,
+};

net/ethtool/netlink.c

···
 	[ETHTOOL_MSG_CHANNELS_GET]	= &ethnl_channels_request_ops,
 	[ETHTOOL_MSG_COALESCE_GET]	= &ethnl_coalesce_request_ops,
 	[ETHTOOL_MSG_PAUSE_GET]		= &ethnl_pause_request_ops,
+	[ETHTOOL_MSG_EEE_GET]		= &ethnl_eee_request_ops,
 };
 
 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
···
 		.cmd	= ETHTOOL_MSG_PAUSE_SET,
 		.flags	= GENL_UNS_ADMIN_PERM,
 		.doit	= ethnl_set_pause,
+	},
+	{
+		.cmd	= ETHTOOL_MSG_EEE_GET,
+		.doit	= ethnl_default_doit,
+		.start	= ethnl_default_start,
+		.dumpit	= ethnl_default_dumpit,
+		.done	= ethnl_default_done,
 	},
 };
 

net/ethtool/netlink.h

···
 extern const struct ethnl_request_ops ethnl_channels_request_ops;
 extern const struct ethnl_request_ops ethnl_coalesce_request_ops;
 extern const struct ethnl_request_ops ethnl_pause_request_ops;
+extern const struct ethnl_request_ops ethnl_eee_request_ops;
 
 int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
 int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);