Merge branch 'ntuple-filters-with-RSS'

Edward Cree says:

====================
ntuple filters with RSS

This series introduces the ability to mark an ethtool steering filter to use
 RSS spreading, and the ability to create and configure multiple RSS contexts
 with different indirection tables, hash keys, and hash fields.
An implementation for the sfc driver (for 7000-series and later SFC NICs) is
 included in patch 2/2.

The anticipated use case of this feature is for steering traffic destined for
 a container (or virtual machine) to the subset of CPUs on which processes in
 the container (or the VM's vCPUs) are bound, while retaining the scalability
 of RSS spreading from the viewpoint inside the container.
The use of both a base queue number (ring_cookie) and indirection table is
 intended to allow re-use of a single RSS context to target multiple sets of
 CPUs.  For instance, if an 8-core system is hosting three containers on CPUs
 [1,2], [3,4] and [6,7], then a single RSS context with an equal-weight [0,1]
 indirection table could be used to target all three containers by setting
 ring_cookie to 1, 3 and 6 on the respective filters.

v2: Initialised ctx in efx_ef10_filter_insert() to avoid (false positive) gcc
 warning.
====================

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

drivers/net/ethernet/sfc/efx.c

@@ -1353,12 +1353,13 @@ static void efx_fini_io(struct efx_nic *efx)
 		pci_disable_device(efx->pci_dev);
 }
 
-void efx_set_default_rx_indir_table(struct efx_nic *efx)
+void efx_set_default_rx_indir_table(struct efx_nic *efx,
+				    struct efx_rss_context *ctx)
 {
 	size_t i;
 
-	for (i = 0; i < ARRAY_SIZE(efx->rx_indir_table); i++)
-		efx->rx_indir_table[i] =
+	for (i = 0; i < ARRAY_SIZE(ctx->rx_indir_table); i++)
+		ctx->rx_indir_table[i] =
 			ethtool_rxfh_indir_default(i, efx->rss_spread);
 }
 
@@ -1739,9 +1740,9 @@ static int efx_probe_nic(struct efx_nic *efx)
 	} while (rc == -EAGAIN);
 
 	if (efx->n_channels > 1)
-		netdev_rss_key_fill(&efx->rx_hash_key,
-				    sizeof(efx->rx_hash_key));
-	efx_set_default_rx_indir_table(efx);
+		netdev_rss_key_fill(efx->rss_context.rx_hash_key,
+				    sizeof(efx->rss_context.rx_hash_key));
+	efx_set_default_rx_indir_table(efx, &efx->rss_context);
 
 	netif_set_real_num_tx_queues(efx->net_dev, efx->n_tx_channels);
 	netif_set_real_num_rx_queues(efx->net_dev, efx->n_rx_channels);
@@ -2700,6 +2701,8 @@ int efx_reset_up(struct efx_nic *efx, enum reset_type method, bool ok)
 			   " VFs may not function\n", rc);
 #endif
 
+	if (efx->type->rx_restore_rss_contexts)
+		efx->type->rx_restore_rss_contexts(efx);
 	down_read(&efx->filter_sem);
 	efx_restore_filters(efx);
 	up_read(&efx->filter_sem);
@@ -3003,6 +3006,7 @@ static int efx_init_struct(struct efx_nic *efx,
 		efx->type->rx_hash_offset - efx->type->rx_prefix_size;
 	efx->rx_packet_ts_offset =
 		efx->type->rx_ts_offset - efx->type->rx_prefix_size;
+	INIT_LIST_HEAD(&efx->rss_context.list);
 	spin_lock_init(&efx->stats_lock);
 	efx->vi_stride = EFX_DEFAULT_VI_STRIDE;
 	efx->num_mac_stats = MC_CMD_MAC_NSTATS;
@@ -3072,6 +3076,55 @@ void efx_update_sw_stats(struct efx_nic *efx, u64 *stats)
 	stats[GENERIC_STAT_rx_noskb_drops] = atomic_read(&efx->n_rx_noskb_drops);
 }
 
+/* RSS contexts.  We're using linked lists and crappy O(n) algorithms, because
+ * (a) this is an infrequent control-plane operation and (b) n is small (max 64)
+ */
+struct efx_rss_context *efx_alloc_rss_context_entry(struct list_head *head)
+{
+	struct efx_rss_context *ctx, *new;
+	u32 id = 1; /* Don't use zero, that refers to the master RSS context */
+
+	/* Search for first gap in the numbering */
+	list_for_each_entry(ctx, head, list) {
+		if (ctx->user_id != id)
+			break;
+		id++;
+		/* Check for wrap.  If this happens, we have nearly 2^32
+		 * allocated RSS contexts, which seems unlikely.
+		 */
+		if (WARN_ON_ONCE(!id))
+			return NULL;
+	}
+
+	/* Create the new entry */
+	new = kmalloc(sizeof(struct efx_rss_context), GFP_KERNEL);
+	if (!new)
+		return NULL;
+	new->context_id = EFX_EF10_RSS_CONTEXT_INVALID;
+	new->rx_hash_udp_4tuple = false;
+
+	/* Insert the new entry into the gap */
+	new->user_id = id;
+	list_add_tail(&new->list, &ctx->list);
+	return new;
+}
+
+struct efx_rss_context *efx_find_rss_context_entry(u32 id, struct list_head *head)
+{
+	struct efx_rss_context *ctx;
+
+	list_for_each_entry(ctx, head, list)
+		if (ctx->user_id == id)
+			return ctx;
+	return NULL;
+}
+
+void efx_free_rss_context_entry(struct efx_rss_context *ctx)
+{
+	list_del(&ctx->list);
+	kfree(ctx);
+}
+
 /**************************************************************************
  *
  * PCI interface

drivers/net/ethernet/sfc/efx.h

@@ -34,7 +34,8 @@ extern unsigned int efx_piobuf_size;
 extern bool efx_separate_tx_channels;
 
 /* RX */
-void efx_set_default_rx_indir_table(struct efx_nic *efx);
+void efx_set_default_rx_indir_table(struct efx_nic *efx,
+				    struct efx_rss_context *ctx);
 void efx_rx_config_page_split(struct efx_nic *efx);
 int efx_probe_rx_queue(struct efx_rx_queue *rx_queue);
 void efx_remove_rx_queue(struct efx_rx_queue *rx_queue);
@@ -182,6 +183,15 @@ static inline void efx_filter_rfs_expire(struct efx_channel *channel) {}
 #endif
 bool efx_filter_is_mc_recipient(const struct efx_filter_spec *spec);
 
+/* RSS contexts */
+struct efx_rss_context *efx_alloc_rss_context_entry(struct list_head *list);
+struct efx_rss_context *efx_find_rss_context_entry(u32 id, struct list_head *list);
+void efx_free_rss_context_entry(struct efx_rss_context *ctx);
+static inline bool efx_rss_active(struct efx_rss_context *ctx)
+{
+	return ctx->context_id != EFX_EF10_RSS_CONTEXT_INVALID;
+}
+
 /* Channels */
 int efx_channel_dummy_op_int(struct efx_channel *channel);
 void efx_channel_dummy_op_void(struct efx_channel *channel);

drivers/net/ethernet/sfc/ethtool.c

@@ -808,7 +808,8 @@ static inline void ip6_fill_mask(__be32 *mask)
 }
 
 static int efx_ethtool_get_class_rule(struct efx_nic *efx,
-				      struct ethtool_rx_flow_spec *rule)
+				      struct ethtool_rx_flow_spec *rule,
+				      u32 *rss_context)
 {
 	struct ethtool_tcpip4_spec *ip_entry = &rule->h_u.tcp_ip4_spec;
 	struct ethtool_tcpip4_spec *ip_mask = &rule->m_u.tcp_ip4_spec;
@@ -964,6 +965,11 @@ static int efx_ethtool_get_class_rule(struct efx_nic *efx,
 		rule->m_ext.vlan_tci = htons(0xfff);
 	}
 
+	if (spec.flags & EFX_FILTER_FLAG_RX_RSS) {
+		rule->flow_type |= FLOW_RSS;
+		*rss_context = spec.rss_context;
+	}
+
 	return rc;
 }
 
@@ -972,19 +978,29 @@ efx_ethtool_get_rxnfc(struct net_device *net_dev,
 		      struct ethtool_rxnfc *info, u32 *rule_locs)
 {
 	struct efx_nic *efx = netdev_priv(net_dev);
+	u32 rss_context = 0;
+	s32 rc;
 
 	switch (info->cmd) {
 	case ETHTOOL_GRXRINGS:
 		info->data = efx->n_rx_channels;
 		return 0;
 
 	case ETHTOOL_GRXFH: {
+		struct efx_rss_context *ctx = &efx->rss_context;
+
+		if (info->flow_type & FLOW_RSS && info->rss_context) {
+			ctx = efx_find_rss_context_entry(info->rss_context,
+							 &efx->rss_context.list);
+			if (!ctx)
+				return -ENOENT;
+		}
 		info->data = 0;
-		if (!efx->rss_active) /* No RSS */
+		if (!efx_rss_active(ctx)) /* No RSS */
 			return 0;
-		switch (info->flow_type) {
+		switch (info->flow_type & ~FLOW_RSS) {
 		case UDP_V4_FLOW:
-			if (efx->rx_hash_udp_4tuple)
+			if (ctx->rx_hash_udp_4tuple)
 				/* fall through */
 		case TCP_V4_FLOW:
 				info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
@@ -995,7 +1011,7 @@ efx_ethtool_get_rxnfc(struct net_device *net_dev,
 			info->data |= RXH_IP_SRC | RXH_IP_DST;
 			break;
 		case UDP_V6_FLOW:
-			if (efx->rx_hash_udp_4tuple)
+			if (ctx->rx_hash_udp_4tuple)
 				/* fall through */
 		case TCP_V6_FLOW:
 				info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
@@ -1023,10 +1039,14 @@ efx_ethtool_get_rxnfc(struct net_device *net_dev,
 	case ETHTOOL_GRXCLSRULE:
 		if (efx_filter_get_rx_id_limit(efx) == 0)
 			return -EOPNOTSUPP;
-		return efx_ethtool_get_class_rule(efx, &info->fs);
+		rc = efx_ethtool_get_class_rule(efx, &info->fs, &rss_context);
+		if (rc < 0)
+			return rc;
+		if (info->fs.flow_type & FLOW_RSS)
+			info->rss_context = rss_context;
+		return 0;
 
-	case ETHTOOL_GRXCLSRLALL: {
-		s32 rc;
+	case ETHTOOL_GRXCLSRLALL:
 		info->data = efx_filter_get_rx_id_limit(efx);
 		if (info->data == 0)
 			return -EOPNOTSUPP;
@@ -1036,7 +1056,6 @@ efx_ethtool_get_rxnfc(struct net_device *net_dev,
 			return rc;
 		info->rule_cnt = rc;
 		return 0;
-	}
 
 	default:
 		return -EOPNOTSUPP;
@@ -1054,7 +1073,8 @@ static inline bool ip6_mask_is_empty(__be32 mask[4])
 }
 
 static int efx_ethtool_set_class_rule(struct efx_nic *efx,
-				      struct ethtool_rx_flow_spec *rule)
+				      struct ethtool_rx_flow_spec *rule,
+				      u32 rss_context)
 {
 	struct ethtool_tcpip4_spec *ip_entry = &rule->h_u.tcp_ip4_spec;
 	struct ethtool_tcpip4_spec *ip_mask = &rule->m_u.tcp_ip4_spec;
@@ -1066,6 +1086,7 @@ static int efx_ethtool_set_class_rule(struct efx_nic *efx,
 	struct ethtool_usrip6_spec *uip6_mask = &rule->m_u.usr_ip6_spec;
 	struct ethhdr *mac_entry = &rule->h_u.ether_spec;
 	struct ethhdr *mac_mask = &rule->m_u.ether_spec;
+	enum efx_filter_flags flags = 0;
 	struct efx_filter_spec spec;
 	int rc;
 
@@ -1084,12 +1105,19 @@ static int efx_ethtool_set_class_rule(struct efx_nic *efx,
 	     rule->m_ext.data[1]))
 		return -EINVAL;
 
-	efx_filter_init_rx(&spec, EFX_FILTER_PRI_MANUAL,
-			   efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,
+	if (efx->rx_scatter)
+		flags |= EFX_FILTER_FLAG_RX_SCATTER;
+	if (rule->flow_type & FLOW_RSS)
+		flags |= EFX_FILTER_FLAG_RX_RSS;
+
+	efx_filter_init_rx(&spec, EFX_FILTER_PRI_MANUAL, flags,
 			   (rule->ring_cookie == RX_CLS_FLOW_DISC) ?
 			   EFX_FILTER_RX_DMAQ_ID_DROP : rule->ring_cookie);
 
-	switch (rule->flow_type & ~FLOW_EXT) {
+	if (rule->flow_type & FLOW_RSS)
+		spec.rss_context = rss_context;
+
+	switch (rule->flow_type & ~(FLOW_EXT | FLOW_RSS)) {
 	case TCP_V4_FLOW:
 	case UDP_V4_FLOW:
 		spec.match_flags = (EFX_FILTER_MATCH_ETHER_TYPE |
@@ -1265,7 +1293,8 @@ static int efx_ethtool_set_rxnfc(struct net_device *net_dev,
 
 	switch (info->cmd) {
 	case ETHTOOL_SRXCLSRLINS:
-		return efx_ethtool_set_class_rule(efx, &info->fs);
+		return efx_ethtool_set_class_rule(efx, &info->fs,
+						  info->rss_context);
 
 	case ETHTOOL_SRXCLSRLDEL:
 		return efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_MANUAL,
@@ -1280,7 +1309,9 @@ static u32 efx_ethtool_get_rxfh_indir_size(struct net_device *net_dev)
 {
 	struct efx_nic *efx = netdev_priv(net_dev);
 
-	return (efx->n_rx_channels == 1) ? 0 : ARRAY_SIZE(efx->rx_indir_table);
+	if (efx->n_rx_channels == 1)
+		return 0;
+	return ARRAY_SIZE(efx->rss_context.rx_indir_table);
 }
 
 static u32 efx_ethtool_get_rxfh_key_size(struct net_device *net_dev)
@@ -1303,9 +1334,11 @@ static int efx_ethtool_get_rxfh(struct net_device *net_dev, u32 *indir, u8 *key,
 	if (hfunc)
 		*hfunc = ETH_RSS_HASH_TOP;
 	if (indir)
-		memcpy(indir, efx->rx_indir_table, sizeof(efx->rx_indir_table));
+		memcpy(indir, efx->rss_context.rx_indir_table,
+		       sizeof(efx->rss_context.rx_indir_table));
 	if (key)
-		memcpy(key, efx->rx_hash_key, efx->type->rx_hash_key_size);
+		memcpy(key, efx->rss_context.rx_hash_key,
+		       efx->type->rx_hash_key_size);
 	return 0;
 }
 
@@ -1321,13 +1354,93 @@ static int efx_ethtool_set_rxfh(struct net_device *net_dev, const u32 *indir,
 		return 0;
 
 	if (!key)
-		key = efx->rx_hash_key;
+		key = efx->rss_context.rx_hash_key;
 	if (!indir)
-		indir = efx->rx_indir_table;
+		indir = efx->rss_context.rx_indir_table;
 
 	return efx->type->rx_push_rss_config(efx, true, indir, key);
 }
 
+static int efx_ethtool_get_rxfh_context(struct net_device *net_dev, u32 *indir,
+					u8 *key, u8 *hfunc, u32 rss_context)
+{
+	struct efx_nic *efx = netdev_priv(net_dev);
+	struct efx_rss_context *ctx;
+	int rc;
+
+	if (!efx->type->rx_pull_rss_context_config)
+		return -EOPNOTSUPP;
+	ctx = efx_find_rss_context_entry(rss_context, &efx->rss_context.list);
+	if (!ctx)
+		return -ENOENT;
+	rc = efx->type->rx_pull_rss_context_config(efx, ctx);
+	if (rc)
+		return rc;
+
+	if (hfunc)
+		*hfunc = ETH_RSS_HASH_TOP;
+	if (indir)
+		memcpy(indir, ctx->rx_indir_table, sizeof(ctx->rx_indir_table));
+	if (key)
+		memcpy(key, ctx->rx_hash_key, efx->type->rx_hash_key_size);
+	return 0;
+}
+
+static int efx_ethtool_set_rxfh_context(struct net_device *net_dev,
+					const u32 *indir, const u8 *key,
+					const u8 hfunc, u32 *rss_context,
+					bool delete)
+{
+	struct efx_nic *efx = netdev_priv(net_dev);
+	struct efx_rss_context *ctx;
+	bool allocated = false;
+	int rc;
+
+	if (!efx->type->rx_push_rss_context_config)
+		return -EOPNOTSUPP;
+	/* Hash function is Toeplitz, cannot be changed */
+	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
+		return -EOPNOTSUPP;
+	if (*rss_context == ETH_RXFH_CONTEXT_ALLOC) {
+		if (delete)
+			/* alloc + delete == Nothing to do */
+			return -EINVAL;
+		ctx = efx_alloc_rss_context_entry(&efx->rss_context.list);
+		if (!ctx)
+			return -ENOMEM;
+		ctx->context_id = EFX_EF10_RSS_CONTEXT_INVALID;
+		/* Initialise indir table and key to defaults */
+		efx_set_default_rx_indir_table(efx, ctx);
+		netdev_rss_key_fill(ctx->rx_hash_key, sizeof(ctx->rx_hash_key));
+		allocated = true;
+	} else {
+		ctx = efx_find_rss_context_entry(*rss_context,
+						 &efx->rss_context.list);
+		if (!ctx)
+			return -ENOENT;
+	}
+
+	if (delete) {
+		/* delete this context */
+		rc = efx->type->rx_push_rss_context_config(efx, ctx, NULL, NULL);
+		if (!rc)
+			efx_free_rss_context_entry(ctx);
+		return rc;
+	}
+
+	if (!key)
+		key = ctx->rx_hash_key;
+	if (!indir)
+		indir = ctx->rx_indir_table;
+
+	rc = efx->type->rx_push_rss_context_config(efx, ctx, indir, key);
+	if (rc && allocated)
+		efx_free_rss_context_entry(ctx);
+	else
+		*rss_context = ctx->user_id;
+	return rc;
+}
+
 static int efx_ethtool_get_ts_info(struct net_device *net_dev,
 				   struct ethtool_ts_info *ts_info)
 {
@@ -1403,6 +1516,8 @@ const struct ethtool_ops efx_ethtool_ops = {
 	.get_rxfh_key_size	= efx_ethtool_get_rxfh_key_size,
 	.get_rxfh		= efx_ethtool_get_rxfh,
 	.set_rxfh		= efx_ethtool_set_rxfh,
+	.get_rxfh_context	= efx_ethtool_get_rxfh_context,
+	.set_rxfh_context	= efx_ethtool_set_rxfh_context,
 	.get_ts_info		= efx_ethtool_get_ts_info,
 	.get_module_info	= efx_ethtool_get_module_info,
 	.get_module_eeprom	= efx_ethtool_get_module_eeprom,