Merge branch 'ehtool-fec-stats'

Jakub Kicinski says:

====================
ethtool: add standard FEC statistics

This set adds uAPI for reporting standard FEC statistics, and
implements it in a handful of drivers.

The statistics are taken from the IEEE standard, with one
extra seemingly popular but not standard statistics added.

The implementation is similar to that of the pause frame
statistics, user requests the stats by setting a bit
(ETHTOOL_FLAG_STATS) in the common ethtool header of
ETHTOOL_MSG_FEC_GET.

Since standard defines the statistics per lane what's
reported is both total and per-lane counters:

 # ethtool -I --show-fec eth0
 FEC parameters for eth0:
 Configured FEC encodings: None
 Active FEC encoding: None
 Statistics:
  corrected_blocks: 256
    Lane 0: 255
    Lane 1: 1
  uncorrectable_blocks: 145
    Lane 0: 128
    Lane 1: 17

v2: check for errors in mlx5 register access
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 76 insertions, 10 deletions

diff --git a/net/ethtool/fec.c b/net/ethtool/fec.c
index 31454b9188bd..8738dafd5417 100644
--- a/net/ethtool/fec.c
+++ b/net/ethtool/fec.c
@@ -13,6 +13,10 @@ struct fec_reply_data {
 	__ETHTOOL_DECLARE_LINK_MODE_MASK(fec_link_modes);
 	u32 active_fec;
 	u8 fec_auto;
+	struct fec_stat_grp {
+		u64 stats[1 + ETHTOOL_MAX_LANES];
+		u8 cnt;
+	} corr, uncorr, corr_bits;
 };
 
 #define FEC_REPDATA(__reply_base) \
@@ -21,7 +25,7 @@ struct fec_reply_data {
 #define ETHTOOL_FEC_MASK	((ETHTOOL_FEC_LLRS << 1) - 1)
 
 const struct nla_policy ethnl_fec_get_policy[ETHTOOL_A_FEC_HEADER + 1] = {
-	[ETHTOOL_A_FEC_HEADER]	= NLA_POLICY_NESTED(ethnl_header_policy),
+	[ETHTOOL_A_FEC_HEADER]	= NLA_POLICY_NESTED(ethnl_header_policy_stats),
 };
 
 static void
@@ -64,6 +68,28 @@ ethtool_link_modes_to_fecparam(struct ethtool_fecparam *fec,
 	return 0;
 }
 
+static void
+fec_stats_recalc(struct fec_stat_grp *grp, struct ethtool_fec_stat *stats)
+{
+	int i;
+
+	if (stats->lanes[0] == ETHTOOL_STAT_NOT_SET) {
+		grp->stats[0] = stats->total;
+		grp->cnt = stats->total != ETHTOOL_STAT_NOT_SET;
+		return;
+	}
+
+	grp->cnt = 1;
+	grp->stats[0] = 0;
+	for (i = 0; i < ETHTOOL_MAX_LANES; i++) {
+		if (stats->lanes[i] == ETHTOOL_STAT_NOT_SET)
+			break;
+
+		grp->stats[0] += stats->lanes[i];
+		grp->stats[grp->cnt++] = stats->lanes[i];
+	}
+}
+
 static int fec_prepare_data(const struct ethnl_req_info *req_base,
 			    struct ethnl_reply_data *reply_base,
 			    struct genl_info *info)
@@ -80,9 +106,19 @@ static int fec_prepare_data(const struct ethnl_req_info *req_base,
 	if (ret < 0)
 		return ret;
 	ret = dev->ethtool_ops->get_fecparam(dev, &fec);
-	ethnl_ops_complete(dev);
 	if (ret)
-		return ret;
+		goto out_complete;
+	if (req_base->flags & ETHTOOL_FLAG_STATS &&
+	    dev->ethtool_ops->get_fec_stats) {
+		struct ethtool_fec_stats stats;
+
+		ethtool_stats_init((u64 *)&stats, sizeof(stats) / 8);
+		dev->ethtool_ops->get_fec_stats(dev, &stats);
+
+		fec_stats_recalc(&data->corr, &stats.corrected_blocks);
+		fec_stats_recalc(&data->uncorr, &stats.uncorrectable_blocks);
+		fec_stats_recalc(&data->corr_bits, &stats.corrected_bits);
+	}
 
 	WARN_ON_ONCE(fec.reserved);
 
@@ -98,7 +134,9 @@ static int fec_prepare_data(const struct ethnl_req_info *req_base,
 	if (data->active_fec == __ETHTOOL_LINK_MODE_MASK_NBITS)
 		data->active_fec = 0;
 
-	return 0;
+out_complete:
+	ethnl_ops_complete(dev);
+	return ret;
 }
 
 static int fec_reply_size(const struct ethnl_req_info *req_base,
@@ -119,9 +157,40 @@ static int fec_reply_size(const struct ethnl_req_info *req_base,
 	len += nla_total_size(sizeof(u8)) +	/* _FEC_AUTO */
 	       nla_total_size(sizeof(u32));	/* _FEC_ACTIVE */
 
+	if (req_base->flags & ETHTOOL_FLAG_STATS)
+		len += 3 * nla_total_size_64bit(sizeof(u64) *
+						(1 + ETHTOOL_MAX_LANES));
+
 	return len;
 }
 
+static int fec_put_stats(struct sk_buff *skb, const struct fec_reply_data *data)
+{
+	struct nlattr *nest;
+
+	nest = nla_nest_start(skb, ETHTOOL_A_FEC_STATS);
+	if (!nest)
+		return -EMSGSIZE;
+
+	if (nla_put_64bit(skb, ETHTOOL_A_FEC_STAT_CORRECTED,
+			  sizeof(u64) * data->corr.cnt,
+			  data->corr.stats, ETHTOOL_A_FEC_STAT_PAD) ||
+	    nla_put_64bit(skb, ETHTOOL_A_FEC_STAT_UNCORR,
+			  sizeof(u64) * data->uncorr.cnt,
+			  data->uncorr.stats, ETHTOOL_A_FEC_STAT_PAD) ||
+	    nla_put_64bit(skb, ETHTOOL_A_FEC_STAT_CORR_BITS,
+			  sizeof(u64) * data->corr_bits.cnt,
+			  data->corr_bits.stats, ETHTOOL_A_FEC_STAT_PAD))
+		goto err_cancel;
+
+	nla_nest_end(skb, nest);
+	return 0;
+
+err_cancel:
+	nla_nest_cancel(skb, nest);
+	return -EMSGSIZE;
+}
+
 static int fec_fill_reply(struct sk_buff *skb,
 			  const struct ethnl_req_info *req_base,
 			  const struct ethnl_reply_data *reply_base)
@@ -142,6 +211,9 @@ static int fec_fill_reply(struct sk_buff *skb,
 	     nla_put_u32(skb, ETHTOOL_A_FEC_ACTIVE, data->active_fec)))
 		return -EMSGSIZE;
 
+	if (req_base->flags & ETHTOOL_FLAG_STATS && fec_put_stats(skb, data))
+		return -EMSGSIZE;
+
 	return 0;
 }
 
diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
index 09998dc5c185..f1967c121278 100644
--- a/net/ethtool/pause.c
+++ b/net/ethtool/pause.c
@@ -21,12 +21,6 @@ const struct nla_policy ethnl_pause_get_policy[] = {
 		NLA_POLICY_NESTED(ethnl_header_policy_stats),
 };
 
-static void ethtool_stats_init(u64 *stats, unsigned int n)
-{
-	while (n--)
-		stats[n] = ETHTOOL_STAT_NOT_SET;
-}
-
 static int pause_prepare_data(const struct ethnl_req_info *req_base,
 			      struct ethnl_reply_data *reply_base,
 			      struct genl_info *info)