Merge branch 'support-setting-lanes-via-ethtool'

Danielle Ratson says:

====================
Support setting lanes via ethtool

Some speeds can be achieved with different number of lanes. For example,
100Gbps can be achieved using two lanes of 50Gbps or four lanes of
25Gbps. This patchset adds a new selector that allows ethtool to
advertise link modes according to their number of lanes and also force a
specific number of lanes when autonegotiation is off.

Advertising all link modes with a speed of 100Gbps that use two lanes:

$ ethtool -s swp1 speed 100000 lanes 2 autoneg on

Forcing a speed of 100Gbps using four lanes:

$ ethtool -s swp1 speed 100000 lanes 4 autoneg off
====================

Link: https://lore.kernel.org/r/20210202180612.325099-1-danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 70 insertions, 138 deletions

diff --git a/net/ethtool/linkmodes.c b/net/ethtool/linkmodes.c
index c5bcb9abc8b9..f9eda596f301 100644
--- a/net/ethtool/linkmodes.c
+++ b/net/ethtool/linkmodes.c
@@ -4,6 +4,8 @@
 #include "common.h"
 #include "bitset.h"
 
+/* LINKMODES_GET */
+
 struct linkmodes_req_info {
 	struct ethnl_req_info		base;
 };
@@ -43,6 +45,9 @@ static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
 		goto out;
 	}
 
+	if (!dev->ethtool_ops->cap_link_lanes_supported)
+		data->ksettings.lanes = 0;
+
 	data->peer_empty =
 		bitmap_empty(data->ksettings.link_modes.lp_advertising,
 			     __ETHTOOL_LINK_MODE_MASK_NBITS);
@@ -63,6 +68,7 @@ static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
 
 	len = nla_total_size(sizeof(u8)) /* LINKMODES_AUTONEG */
 		+ nla_total_size(sizeof(u32)) /* LINKMODES_SPEED */
+		+ nla_total_size(sizeof(u32)) /* LINKMODES_LANES */
 		+ nla_total_size(sizeof(u8)) /* LINKMODES_DUPLEX */
 		+ 0;
 	ret = ethnl_bitset_size(ksettings->link_modes.advertising,
@@ -123,6 +129,10 @@ static int linkmodes_fill_reply(struct sk_buff *skb,
 	    nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
 		return -EMSGSIZE;
 
+	if (ksettings->lanes &&
+	    nla_put_u32(skb, ETHTOOL_A_LINKMODES_LANES, ksettings->lanes))
+		return -EMSGSIZE;
+
 	if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED &&
 	    nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
 		       lsettings->master_slave_cfg))
@@ -150,122 +160,6 @@ const struct ethnl_request_ops ethnl_linkmodes_request_ops = {
 
 /* LINKMODES_SET */
 
-struct link_mode_info {
-	int				speed;
-	u8				duplex;
-};
-
-#define __DEFINE_LINK_MODE_PARAMS(_speed, _type, _duplex) \
-	[ETHTOOL_LINK_MODE(_speed, _type, _duplex)] = { \
-		.speed	= SPEED_ ## _speed, \
-		.duplex	= __DUPLEX_ ## _duplex \
-	}
-#define __DUPLEX_Half DUPLEX_HALF
-#define __DUPLEX_Full DUPLEX_FULL
-#define __DEFINE_SPECIAL_MODE_PARAMS(_mode) \
-	[ETHTOOL_LINK_MODE_ ## _mode ## _BIT] = { \
-		.speed	= SPEED_UNKNOWN, \
-		.duplex	= DUPLEX_UNKNOWN, \
-	}
-
-static const struct link_mode_info link_mode_params[] = {
-	__DEFINE_LINK_MODE_PARAMS(10, T, Half),
-	__DEFINE_LINK_MODE_PARAMS(10, T, Full),
-	__DEFINE_LINK_MODE_PARAMS(100, T, Half),
-	__DEFINE_LINK_MODE_PARAMS(100, T, Full),
-	__DEFINE_LINK_MODE_PARAMS(1000, T, Half),
-	__DEFINE_LINK_MODE_PARAMS(1000, T, Full),
-	__DEFINE_SPECIAL_MODE_PARAMS(Autoneg),
-	__DEFINE_SPECIAL_MODE_PARAMS(TP),
-	__DEFINE_SPECIAL_MODE_PARAMS(AUI),
-	__DEFINE_SPECIAL_MODE_PARAMS(MII),
-	__DEFINE_SPECIAL_MODE_PARAMS(FIBRE),
-	__DEFINE_SPECIAL_MODE_PARAMS(BNC),
-	__DEFINE_LINK_MODE_PARAMS(10000, T, Full),
-	__DEFINE_SPECIAL_MODE_PARAMS(Pause),
-	__DEFINE_SPECIAL_MODE_PARAMS(Asym_Pause),
-	__DEFINE_LINK_MODE_PARAMS(2500, X, Full),
-	__DEFINE_SPECIAL_MODE_PARAMS(Backplane),
-	__DEFINE_LINK_MODE_PARAMS(1000, KX, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, KX4, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, KR, Full),
-	[ETHTOOL_LINK_MODE_10000baseR_FEC_BIT] = {
-		.speed	= SPEED_10000,
-		.duplex = DUPLEX_FULL,
-	},
-	__DEFINE_LINK_MODE_PARAMS(20000, MLD2, Full),
-	__DEFINE_LINK_MODE_PARAMS(20000, KR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(40000, KR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(40000, CR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(40000, SR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(40000, LR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(56000, KR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(56000, CR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(56000, SR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(56000, LR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(25000, CR, Full),
-	__DEFINE_LINK_MODE_PARAMS(25000, KR, Full),
-	__DEFINE_LINK_MODE_PARAMS(25000, SR, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, CR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, KR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, KR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, SR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, CR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, LR4_ER4, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, SR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(1000, X, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, CR, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, SR, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, LR, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, LRM, Full),
-	__DEFINE_LINK_MODE_PARAMS(10000, ER, Full),
-	__DEFINE_LINK_MODE_PARAMS(2500, T, Full),
-	__DEFINE_LINK_MODE_PARAMS(5000, T, Full),
-	__DEFINE_SPECIAL_MODE_PARAMS(FEC_NONE),
-	__DEFINE_SPECIAL_MODE_PARAMS(FEC_RS),
-	__DEFINE_SPECIAL_MODE_PARAMS(FEC_BASER),
-	__DEFINE_LINK_MODE_PARAMS(50000, KR, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, SR, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, CR, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, LR_ER_FR, Full),
-	__DEFINE_LINK_MODE_PARAMS(50000, DR, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, KR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, SR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, CR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, LR2_ER2_FR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, DR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, KR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, SR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, LR4_ER4_FR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, DR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, CR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(100, T1, Full),
-	__DEFINE_LINK_MODE_PARAMS(1000, T1, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, KR8, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, SR8, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, LR8_ER8_FR8, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, DR8, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, CR8, Full),
-	__DEFINE_SPECIAL_MODE_PARAMS(FEC_LLRS),
-	__DEFINE_LINK_MODE_PARAMS(100000, KR, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, SR, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, LR_ER_FR, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, DR, Full),
-	__DEFINE_LINK_MODE_PARAMS(100000, CR, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, KR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, SR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, LR2_ER2_FR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, DR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(200000, CR2, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, KR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, SR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, LR4_ER4_FR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, DR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(400000, CR4, Full),
-	__DEFINE_LINK_MODE_PARAMS(100, FX, Half),
-	__DEFINE_LINK_MODE_PARAMS(100, FX, Full),
-};
-
 const struct nla_policy ethnl_linkmodes_set_policy[] = {
 	[ETHTOOL_A_LINKMODES_HEADER]		=
 		NLA_POLICY_NESTED(ethnl_header_policy),
@@ -274,25 +168,23 @@ const struct nla_policy ethnl_linkmodes_set_policy[] = {
 	[ETHTOOL_A_LINKMODES_SPEED]		= { .type = NLA_U32 },
 	[ETHTOOL_A_LINKMODES_DUPLEX]		= { .type = NLA_U8 },
 	[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]	= { .type = NLA_U8 },
+	[ETHTOOL_A_LINKMODES_LANES]		= NLA_POLICY_RANGE(NLA_U32, 1, 8),
 };
 
-/* Set advertised link modes to all supported modes matching requested speed
- * and duplex values. Called when autonegotiation is on, speed or duplex is
- * requested but no link mode change. This is done in userspace with ioctl()
- * interface, move it into kernel for netlink.
+/* Set advertised link modes to all supported modes matching requested speed,
+ * lanes and duplex values. Called when autonegotiation is on, speed, lanes or
+ * duplex is requested but no link mode change. This is done in userspace with
+ * ioctl() interface, move it into kernel for netlink.
  * Returns true if advertised modes bitmap was modified.
  */
 static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
-				 bool req_speed, bool req_duplex)
+				 bool req_speed, bool req_lanes, bool req_duplex)
 {
 	unsigned long *advertising = ksettings->link_modes.advertising;
 	unsigned long *supported = ksettings->link_modes.supported;
 	DECLARE_BITMAP(old_adv, __ETHTOOL_LINK_MODE_MASK_NBITS);
 	unsigned int i;
 
-	BUILD_BUG_ON(ARRAY_SIZE(link_mode_params) !=
-		     __ETHTOOL_LINK_MODE_MASK_NBITS);
-
 	bitmap_copy(old_adv, advertising, __ETHTOOL_LINK_MODE_MASK_NBITS);
 
 	for (i = 0; i < __ETHTOOL_LINK_MODE_MASK_NBITS; i++) {
@@ -302,6 +194,7 @@ static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
 			continue;
 		if (test_bit(i, supported) &&
 		    (!req_speed || info->speed == ksettings->base.speed) &&
+		    (!req_lanes || info->lanes == ksettings->lanes) &&
 		    (!req_duplex || info->duplex == ksettings->base.duplex))
 			set_bit(i, advertising);
 		else
@@ -325,38 +218,72 @@ static bool ethnl_validate_master_slave_cfg(u8 cfg)
 	return false;
 }
 
+static int ethnl_check_linkmodes(struct genl_info *info, struct nlattr **tb)
+{
+	const struct nlattr *master_slave_cfg, *lanes_cfg;
+
+	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
+	if (master_slave_cfg &&
+	    !ethnl_validate_master_slave_cfg(nla_get_u8(master_slave_cfg))) {
+		NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
+				    "master/slave value is invalid");
+		return -EOPNOTSUPP;
+	}
+
+	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
+	if (lanes_cfg && !is_power_of_2(nla_get_u32(lanes_cfg))) {
+		NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
+				    "lanes value is invalid");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
 				  struct ethtool_link_ksettings *ksettings,
-				  bool *mod)
+				  bool *mod, const struct net_device *dev)
 {
 	struct ethtool_link_settings *lsettings = &ksettings->base;
-	bool req_speed, req_duplex;
-	const struct nlattr *master_slave_cfg;
+	bool req_speed, req_lanes, req_duplex;
+	const struct nlattr *master_slave_cfg, *lanes_cfg;
 	int ret;
 
 	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
 	if (master_slave_cfg) {
-		u8 cfg = nla_get_u8(master_slave_cfg);
-
 		if (lsettings->master_slave_cfg == MASTER_SLAVE_CFG_UNSUPPORTED) {
 			NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
 					    "master/slave configuration not supported by device");
 			return -EOPNOTSUPP;
 		}
-
-		if (!ethnl_validate_master_slave_cfg(cfg)) {
-			NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
-					    "master/slave value is invalid");
-			return -EOPNOTSUPP;
-		}
 	}
 
 	*mod = false;
 	req_speed = tb[ETHTOOL_A_LINKMODES_SPEED];
+	req_lanes = tb[ETHTOOL_A_LINKMODES_LANES];
 	req_duplex = tb[ETHTOOL_A_LINKMODES_DUPLEX];
 
 	ethnl_update_u8(&lsettings->autoneg, tb[ETHTOOL_A_LINKMODES_AUTONEG],
 			mod);
+
+	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
+	if (lanes_cfg) {
+		/* If autoneg is off and lanes parameter is not supported by the
+		 * driver, return an error.
+		 */
+		if (!lsettings->autoneg &&
+		    !dev->ethtool_ops->cap_link_lanes_supported) {
+			NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
+					    "lanes configuration not supported by device");
+			return -EOPNOTSUPP;
+		}
+	} else if (!lsettings->autoneg) {
+		/* If autoneg is off and lanes parameter is not passed from user,
+		 * set the lanes parameter to 0.
+		 */
+		ksettings->lanes = 0;
+	}
+
 	ret = ethnl_update_bitset(ksettings->link_modes.advertising,
 				  __ETHTOOL_LINK_MODE_MASK_NBITS,
 				  tb[ETHTOOL_A_LINKMODES_OURS], link_mode_names,
@@ -365,13 +292,14 @@ static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
 		return ret;
 	ethnl_update_u32(&lsettings->speed, tb[ETHTOOL_A_LINKMODES_SPEED],
 			 mod);
+	ethnl_update_u32(&ksettings->lanes, lanes_cfg, mod);
 	ethnl_update_u8(&lsettings->duplex, tb[ETHTOOL_A_LINKMODES_DUPLEX],
 			mod);
 	ethnl_update_u8(&lsettings->master_slave_cfg, master_slave_cfg, mod);
 
 	if (!tb[ETHTOOL_A_LINKMODES_OURS] && lsettings->autoneg &&
-	    (req_speed || req_duplex) &&
-	    ethnl_auto_linkmodes(ksettings, req_speed, req_duplex))
+	    (req_speed || req_lanes || req_duplex) &&
+	    ethnl_auto_linkmodes(ksettings, req_speed, req_lanes, req_duplex))
 		*mod = true;
 
 	return 0;
@@ -386,6 +314,10 @@ int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info)
 	bool mod = false;
 	int ret;
 
+	ret = ethnl_check_linkmodes(info, tb);
+	if (ret < 0)
+		return ret;
+
 	ret = ethnl_parse_header_dev_get(&req_info,
 					 tb[ETHTOOL_A_LINKMODES_HEADER],
 					 genl_info_net(info), info->extack,
@@ -409,7 +341,7 @@ int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info)
 		goto out_ops;
 	}
 
-	ret = ethnl_update_linkmodes(info, tb, &ksettings, &mod);
+	ret = ethnl_update_linkmodes(info, tb, &ksettings, &mod, dev);
 	if (ret < 0)
 		goto out_ops;