1 files changed, 727 insertions, 0 deletions

diff --git a/drivers/net/ethernet/sfc/filter.c b/drivers/net/ethernet/sfc/filter.c
new file mode 100644
index 000000000000..2b9636f96e05
--- /dev/null
+++ b/drivers/net/ethernet/sfc/filter.c
@@ -0,0 +1,727 @@
+/****************************************************************************
+ * Driver for Solarflare Solarstorm network controllers and boards
+ * Copyright 2005-2010 Solarflare Communications Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+
+#include <linux/in.h>
+#include <net/ip.h>
+#include "efx.h"
+#include "filter.h"
+#include "io.h"
+#include "nic.h"
+#include "regs.h"
+
+/* "Fudge factors" - difference between programmed value and actual depth.
+ * Due to pipelined implementation we need to program H/W with a value that
+ * is larger than the hop limit we want.
+ */
+#define FILTER_CTL_SRCH_FUDGE_WILD 3
+#define FILTER_CTL_SRCH_FUDGE_FULL 1
+
+/* Hard maximum hop limit.  Hardware will time-out beyond 200-something.
+ * We also need to avoid infinite loops in efx_filter_search() when the
+ * table is full.
+ */
+#define FILTER_CTL_SRCH_MAX 200
+
+/* Don't try very hard to find space for performance hints, as this is
+ * counter-productive. */
+#define FILTER_CTL_SRCH_HINT_MAX 5
+
+enum efx_filter_table_id {
+	EFX_FILTER_TABLE_RX_IP = 0,
+	EFX_FILTER_TABLE_RX_MAC,
+	EFX_FILTER_TABLE_COUNT,
+};
+
+struct efx_filter_table {
+	enum efx_filter_table_id id;
+	u32		offset;		/* address of table relative to BAR */
+	unsigned	size;		/* number of entries */
+	unsigned	step;		/* step between entries */
+	unsigned	used;		/* number currently used */
+	unsigned long	*used_bitmap;
+	struct efx_filter_spec *spec;
+	unsigned	search_depth[EFX_FILTER_TYPE_COUNT];
+};
+
+struct efx_filter_state {
+	spinlock_t	lock;
+	struct efx_filter_table table[EFX_FILTER_TABLE_COUNT];
+#ifdef CONFIG_RFS_ACCEL
+	u32		*rps_flow_id;
+	unsigned	rps_expire_index;
+#endif
+};
+
+/* The filter hash function is LFSR polynomial x^16 + x^3 + 1 of a 32-bit
+ * key derived from the n-tuple.  The initial LFSR state is 0xffff. */
+static u16 efx_filter_hash(u32 key)
+{
+	u16 tmp;
+
+	/* First 16 rounds */
+	tmp = 0x1fff ^ key >> 16;
+	tmp = tmp ^ tmp >> 3 ^ tmp >> 6;
+	tmp = tmp ^ tmp >> 9;
+	/* Last 16 rounds */
+	tmp = tmp ^ tmp << 13 ^ key;
+	tmp = tmp ^ tmp >> 3 ^ tmp >> 6;
+	return tmp ^ tmp >> 9;
+}
+
+/* To allow for hash collisions, filter search continues at these
+ * increments from the first possible entry selected by the hash. */
+static u16 efx_filter_increment(u32 key)
+{
+	return key * 2 - 1;
+}
+
+static enum efx_filter_table_id
+efx_filter_spec_table_id(const struct efx_filter_spec *spec)
+{
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_TCP_FULL >> 2));
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_TCP_WILD >> 2));
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_UDP_FULL >> 2));
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_IP != (EFX_FILTER_UDP_WILD >> 2));
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_MAC != (EFX_FILTER_MAC_FULL >> 2));
+	BUILD_BUG_ON(EFX_FILTER_TABLE_RX_MAC != (EFX_FILTER_MAC_WILD >> 2));
+	EFX_BUG_ON_PARANOID(spec->type == EFX_FILTER_UNSPEC);
+	return spec->type >> 2;
+}
+
+static struct efx_filter_table *
+efx_filter_spec_table(struct efx_filter_state *state,
+		      const struct efx_filter_spec *spec)
+{
+	if (spec->type == EFX_FILTER_UNSPEC)
+		return NULL;
+	else
+		return &state->table[efx_filter_spec_table_id(spec)];
+}
+
+static void efx_filter_table_reset_search_depth(struct efx_filter_table *table)
+{
+	memset(table->search_depth, 0, sizeof(table->search_depth));
+}
+
+static void efx_filter_push_rx_limits(struct efx_nic *efx)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_table *table;
+	efx_oword_t filter_ctl;
+
+	efx_reado(efx, &filter_ctl, FR_BZ_RX_FILTER_CTL);
+
+	table = &state->table[EFX_FILTER_TABLE_RX_IP];
+	EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_TCP_FULL_SRCH_LIMIT,
+			    table->search_depth[EFX_FILTER_TCP_FULL] +
+			    FILTER_CTL_SRCH_FUDGE_FULL);
+	EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_TCP_WILD_SRCH_LIMIT,
+			    table->search_depth[EFX_FILTER_TCP_WILD] +
+			    FILTER_CTL_SRCH_FUDGE_WILD);
+	EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_UDP_FULL_SRCH_LIMIT,
+			    table->search_depth[EFX_FILTER_UDP_FULL] +
+			    FILTER_CTL_SRCH_FUDGE_FULL);
+	EFX_SET_OWORD_FIELD(filter_ctl, FRF_BZ_UDP_WILD_SRCH_LIMIT,
+			    table->search_depth[EFX_FILTER_UDP_WILD] +
+			    FILTER_CTL_SRCH_FUDGE_WILD);
+
+	table = &state->table[EFX_FILTER_TABLE_RX_MAC];
+	if (table->size) {
+		EFX_SET_OWORD_FIELD(
+			filter_ctl, FRF_CZ_ETHERNET_FULL_SEARCH_LIMIT,
+			table->search_depth[EFX_FILTER_MAC_FULL] +
+			FILTER_CTL_SRCH_FUDGE_FULL);
+		EFX_SET_OWORD_FIELD(
+			filter_ctl, FRF_CZ_ETHERNET_WILDCARD_SEARCH_LIMIT,
+			table->search_depth[EFX_FILTER_MAC_WILD] +
+			FILTER_CTL_SRCH_FUDGE_WILD);
+	}
+
+	efx_writeo(efx, &filter_ctl, FR_BZ_RX_FILTER_CTL);
+}
+
+static inline void __efx_filter_set_ipv4(struct efx_filter_spec *spec,
+					 __be32 host1, __be16 port1,
+					 __be32 host2, __be16 port2)
+{
+	spec->data[0] = ntohl(host1) << 16 | ntohs(port1);
+	spec->data[1] = ntohs(port2) << 16 | ntohl(host1) >> 16;
+	spec->data[2] = ntohl(host2);
+}
+
+/**
+ * efx_filter_set_ipv4_local - specify IPv4 host, transport protocol and port
+ * @spec: Specification to initialise
+ * @proto: Transport layer protocol number
+ * @host: Local host address (network byte order)
+ * @port: Local port (network byte order)
+ */
+int efx_filter_set_ipv4_local(struct efx_filter_spec *spec, u8 proto,
+			      __be32 host, __be16 port)
+{
+	__be32 host1;
+	__be16 port1;
+
+	EFX_BUG_ON_PARANOID(!(spec->flags & EFX_FILTER_FLAG_RX));
+
+	/* This cannot currently be combined with other filtering */
+	if (spec->type != EFX_FILTER_UNSPEC)
+		return -EPROTONOSUPPORT;
+
+	if (port == 0)
+		return -EINVAL;
+
+	switch (proto) {
+	case IPPROTO_TCP:
+		spec->type = EFX_FILTER_TCP_WILD;
+		break;
+	case IPPROTO_UDP:
+		spec->type = EFX_FILTER_UDP_WILD;
+		break;
+	default:
+		return -EPROTONOSUPPORT;
+	}
+
+	/* Filter is constructed in terms of source and destination,
+	 * with the odd wrinkle that the ports are swapped in a UDP
+	 * wildcard filter.  We need to convert from local and remote
+	 * (= zero for wildcard) addresses.
+	 */
+	host1 = 0;
+	if (proto != IPPROTO_UDP) {
+		port1 = 0;
+	} else {
+		port1 = port;
+		port = 0;
+	}
+
+	__efx_filter_set_ipv4(spec, host1, port1, host, port);
+	return 0;
+}
+
+/**
+ * efx_filter_set_ipv4_full - specify IPv4 hosts, transport protocol and ports
+ * @spec: Specification to initialise
+ * @proto: Transport layer protocol number
+ * @host: Local host address (network byte order)
+ * @port: Local port (network byte order)
+ * @rhost: Remote host address (network byte order)
+ * @rport: Remote port (network byte order)
+ */
+int efx_filter_set_ipv4_full(struct efx_filter_spec *spec, u8 proto,
+			     __be32 host, __be16 port,
+			     __be32 rhost, __be16 rport)
+{
+	EFX_BUG_ON_PARANOID(!(spec->flags & EFX_FILTER_FLAG_RX));
+
+	/* This cannot currently be combined with other filtering */
+	if (spec->type != EFX_FILTER_UNSPEC)
+		return -EPROTONOSUPPORT;
+
+	if (port == 0 || rport == 0)
+		return -EINVAL;
+
+	switch (proto) {
+	case IPPROTO_TCP:
+		spec->type = EFX_FILTER_TCP_FULL;
+		break;
+	case IPPROTO_UDP:
+		spec->type = EFX_FILTER_UDP_FULL;
+		break;
+	default:
+		return -EPROTONOSUPPORT;
+	}
+
+	__efx_filter_set_ipv4(spec, rhost, rport, host, port);
+	return 0;
+}
+
+/**
+ * efx_filter_set_eth_local - specify local Ethernet address and optional VID
+ * @spec: Specification to initialise
+ * @vid: VLAN ID to match, or %EFX_FILTER_VID_UNSPEC
+ * @addr: Local Ethernet MAC address
+ */
+int efx_filter_set_eth_local(struct efx_filter_spec *spec,
+			     u16 vid, const u8 *addr)
+{
+	EFX_BUG_ON_PARANOID(!(spec->flags & EFX_FILTER_FLAG_RX));
+
+	/* This cannot currently be combined with other filtering */
+	if (spec->type != EFX_FILTER_UNSPEC)
+		return -EPROTONOSUPPORT;
+
+	if (vid == EFX_FILTER_VID_UNSPEC) {
+		spec->type = EFX_FILTER_MAC_WILD;
+		spec->data[0] = 0;
+	} else {
+		spec->type = EFX_FILTER_MAC_FULL;
+		spec->data[0] = vid;
+	}
+
+	spec->data[1] = addr[2] << 24 | addr[3] << 16 | addr[4] << 8 | addr[5];
+	spec->data[2] = addr[0] << 8 | addr[1];
+	return 0;
+}
+
+/* Build a filter entry and return its n-tuple key. */
+static u32 efx_filter_build(efx_oword_t *filter, struct efx_filter_spec *spec)
+{
+	u32 data3;
+
+	switch (efx_filter_spec_table_id(spec)) {
+	case EFX_FILTER_TABLE_RX_IP: {
+		bool is_udp = (spec->type == EFX_FILTER_UDP_FULL ||
+			       spec->type == EFX_FILTER_UDP_WILD);
+		EFX_POPULATE_OWORD_7(
+			*filter,
+			FRF_BZ_RSS_EN,
+			!!(spec->flags & EFX_FILTER_FLAG_RX_RSS),
+			FRF_BZ_SCATTER_EN,
+			!!(spec->flags & EFX_FILTER_FLAG_RX_SCATTER),
+			FRF_BZ_TCP_UDP, is_udp,
+			FRF_BZ_RXQ_ID, spec->dmaq_id,
+			EFX_DWORD_2, spec->data[2],
+			EFX_DWORD_1, spec->data[1],
+			EFX_DWORD_0, spec->data[0]);
+		data3 = is_udp;
+		break;
+	}
+
+	case EFX_FILTER_TABLE_RX_MAC: {
+		bool is_wild = spec->type == EFX_FILTER_MAC_WILD;
+		EFX_POPULATE_OWORD_8(
+			*filter,
+			FRF_CZ_RMFT_RSS_EN,
+			!!(spec->flags & EFX_FILTER_FLAG_RX_RSS),
+			FRF_CZ_RMFT_SCATTER_EN,
+			!!(spec->flags & EFX_FILTER_FLAG_RX_SCATTER),
+			FRF_CZ_RMFT_IP_OVERRIDE,
+			!!(spec->flags & EFX_FILTER_FLAG_RX_OVERRIDE_IP),
+			FRF_CZ_RMFT_RXQ_ID, spec->dmaq_id,
+			FRF_CZ_RMFT_WILDCARD_MATCH, is_wild,
+			FRF_CZ_RMFT_DEST_MAC_HI, spec->data[2],
+			FRF_CZ_RMFT_DEST_MAC_LO, spec->data[1],
+			FRF_CZ_RMFT_VLAN_ID, spec->data[0]);
+		data3 = is_wild;
+		break;
+	}
+
+	default:
+		BUG();
+	}
+
+	return spec->data[0] ^ spec->data[1] ^ spec->data[2] ^ data3;
+}
+
+static bool efx_filter_equal(const struct efx_filter_spec *left,
+			     const struct efx_filter_spec *right)
+{
+	if (left->type != right->type ||
+	    memcmp(left->data, right->data, sizeof(left->data)))
+		return false;
+
+	return true;
+}
+
+static int efx_filter_search(struct efx_filter_table *table,
+			     struct efx_filter_spec *spec, u32 key,
+			     bool for_insert, int *depth_required)
+{
+	unsigned hash, incr, filter_idx, depth, depth_max;
+
+	hash = efx_filter_hash(key);
+	incr = efx_filter_increment(key);
+
+	filter_idx = hash & (table->size - 1);
+	depth = 1;
+	depth_max = (for_insert ?
+		     (spec->priority <= EFX_FILTER_PRI_HINT ?
+		      FILTER_CTL_SRCH_HINT_MAX : FILTER_CTL_SRCH_MAX) :
+		     table->search_depth[spec->type]);
+
+	for (;;) {
+		/* Return success if entry is used and matches this spec
+		 * or entry is unused and we are trying to insert.
+		 */
+		if (test_bit(filter_idx, table->used_bitmap) ?
+		    efx_filter_equal(spec, &table->spec[filter_idx]) :
+		    for_insert) {
+			*depth_required = depth;
+			return filter_idx;
+		}
+
+		/* Return failure if we reached the maximum search depth */
+		if (depth == depth_max)
+			return for_insert ? -EBUSY : -ENOENT;
+
+		filter_idx = (filter_idx + incr) & (table->size - 1);
+		++depth;
+	}
+}
+
+/* Construct/deconstruct external filter IDs */
+
+static inline int
+efx_filter_make_id(enum efx_filter_table_id table_id, unsigned index)
+{
+	return table_id << 16 | index;
+}
+
+/**
+ * efx_filter_insert_filter - add or replace a filter
+ * @efx: NIC in which to insert the filter
+ * @spec: Specification for the filter
+ * @replace: Flag for whether the specified filter may replace a filter
+ *	with an identical match expression and equal or lower priority
+ *
+ * On success, return the filter ID.
+ * On failure, return a negative error code.
+ */
+int efx_filter_insert_filter(struct efx_nic *efx, struct efx_filter_spec *spec,
+			     bool replace)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_table *table = efx_filter_spec_table(state, spec);
+	struct efx_filter_spec *saved_spec;
+	efx_oword_t filter;
+	int filter_idx, depth;
+	u32 key;
+	int rc;
+
+	if (!table || table->size == 0)
+		return -EINVAL;
+
+	key = efx_filter_build(&filter, spec);
+
+	netif_vdbg(efx, hw, efx->net_dev,
+		   "%s: type %d search_depth=%d", __func__, spec->type,
+		   table->search_depth[spec->type]);
+
+	spin_lock_bh(&state->lock);
+
+	rc = efx_filter_search(table, spec, key, true, &depth);
+	if (rc < 0)
+		goto out;
+	filter_idx = rc;
+	BUG_ON(filter_idx >= table->size);
+	saved_spec = &table->spec[filter_idx];
+
+	if (test_bit(filter_idx, table->used_bitmap)) {
+		/* Should we replace the existing filter? */
+		if (!replace) {
+			rc = -EEXIST;
+			goto out;
+		}
+		if (spec->priority < saved_spec->priority) {
+			rc = -EPERM;
+			goto out;
+		}
+	} else {
+		__set_bit(filter_idx, table->used_bitmap);
+		++table->used;
+	}
+	*saved_spec = *spec;
+
+	if (table->search_depth[spec->type] < depth) {
+		table->search_depth[spec->type] = depth;
+		efx_filter_push_rx_limits(efx);
+	}
+
+	efx_writeo(efx, &filter, table->offset + table->step * filter_idx);
+
+	netif_vdbg(efx, hw, efx->net_dev,
+		   "%s: filter type %d index %d rxq %u set",
+		   __func__, spec->type, filter_idx, spec->dmaq_id);
+	rc = efx_filter_make_id(table->id, filter_idx);
+
+out:
+	spin_unlock_bh(&state->lock);
+	return rc;
+}
+
+static void efx_filter_table_clear_entry(struct efx_nic *efx,
+					 struct efx_filter_table *table,
+					 int filter_idx)
+{
+	static efx_oword_t filter;
+
+	if (test_bit(filter_idx, table->used_bitmap)) {
+		__clear_bit(filter_idx, table->used_bitmap);
+		--table->used;
+		memset(&table->spec[filter_idx], 0, sizeof(table->spec[0]));
+
+		efx_writeo(efx, &filter,
+			   table->offset + table->step * filter_idx);
+	}
+}
+
+/**
+ * efx_filter_remove_filter - remove a filter by specification
+ * @efx: NIC from which to remove the filter
+ * @spec: Specification for the filter
+ *
+ * On success, return zero.
+ * On failure, return a negative error code.
+ */
+int efx_filter_remove_filter(struct efx_nic *efx, struct efx_filter_spec *spec)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_table *table = efx_filter_spec_table(state, spec);
+	struct efx_filter_spec *saved_spec;
+	efx_oword_t filter;
+	int filter_idx, depth;
+	u32 key;
+	int rc;
+
+	if (!table)
+		return -EINVAL;
+
+	key = efx_filter_build(&filter, spec);
+
+	spin_lock_bh(&state->lock);
+
+	rc = efx_filter_search(table, spec, key, false, &depth);
+	if (rc < 0)
+		goto out;
+	filter_idx = rc;
+	saved_spec = &table->spec[filter_idx];
+
+	if (spec->priority < saved_spec->priority) {
+		rc = -EPERM;
+		goto out;
+	}
+
+	efx_filter_table_clear_entry(efx, table, filter_idx);
+	if (table->used == 0)
+		efx_filter_table_reset_search_depth(table);
+	rc = 0;
+
+out:
+	spin_unlock_bh(&state->lock);
+	return rc;
+}
+
+static void efx_filter_table_clear(struct efx_nic *efx,
+				   enum efx_filter_table_id table_id,
+				   enum efx_filter_priority priority)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_table *table = &state->table[table_id];
+	int filter_idx;
+
+	spin_lock_bh(&state->lock);
+
+	for (filter_idx = 0; filter_idx < table->size; ++filter_idx)
+		if (table->spec[filter_idx].priority <= priority)
+			efx_filter_table_clear_entry(efx, table, filter_idx);
+	if (table->used == 0)
+		efx_filter_table_reset_search_depth(table);
+
+	spin_unlock_bh(&state->lock);
+}
+
+/**
+ * efx_filter_clear_rx - remove RX filters by priority
+ * @efx: NIC from which to remove the filters
+ * @priority: Maximum priority to remove
+ */
+void efx_filter_clear_rx(struct efx_nic *efx, enum efx_filter_priority priority)
+{
+	efx_filter_table_clear(efx, EFX_FILTER_TABLE_RX_IP, priority);
+	efx_filter_table_clear(efx, EFX_FILTER_TABLE_RX_MAC, priority);
+}
+
+/* Restore filter stater after reset */
+void efx_restore_filters(struct efx_nic *efx)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	enum efx_filter_table_id table_id;
+	struct efx_filter_table *table;
+	efx_oword_t filter;
+	int filter_idx;
+
+	spin_lock_bh(&state->lock);
+
+	for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) {
+		table = &state->table[table_id];
+		for (filter_idx = 0; filter_idx < table->size; filter_idx++) {
+			if (!test_bit(filter_idx, table->used_bitmap))
+				continue;
+			efx_filter_build(&filter, &table->spec[filter_idx]);
+			efx_writeo(efx, &filter,
+				   table->offset + table->step * filter_idx);
+		}
+	}
+
+	efx_filter_push_rx_limits(efx);
+
+	spin_unlock_bh(&state->lock);
+}
+
+int efx_probe_filters(struct efx_nic *efx)
+{
+	struct efx_filter_state *state;
+	struct efx_filter_table *table;
+	unsigned table_id;
+
+	state = kzalloc(sizeof(*efx->filter_state), GFP_KERNEL);
+	if (!state)
+		return -ENOMEM;
+	efx->filter_state = state;
+
+	spin_lock_init(&state->lock);
+
+	if (efx_nic_rev(efx) >= EFX_REV_FALCON_B0) {
+#ifdef CONFIG_RFS_ACCEL
+		state->rps_flow_id = kcalloc(FR_BZ_RX_FILTER_TBL0_ROWS,
+					     sizeof(*state->rps_flow_id),
+					     GFP_KERNEL);
+		if (!state->rps_flow_id)
+			goto fail;
+#endif
+		table = &state->table[EFX_FILTER_TABLE_RX_IP];
+		table->id = EFX_FILTER_TABLE_RX_IP;
+		table->offset = FR_BZ_RX_FILTER_TBL0;
+		table->size = FR_BZ_RX_FILTER_TBL0_ROWS;
+		table->step = FR_BZ_RX_FILTER_TBL0_STEP;
+	}
+
+	if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0) {
+		table = &state->table[EFX_FILTER_TABLE_RX_MAC];
+		table->id = EFX_FILTER_TABLE_RX_MAC;
+		table->offset = FR_CZ_RX_MAC_FILTER_TBL0;
+		table->size = FR_CZ_RX_MAC_FILTER_TBL0_ROWS;
+		table->step = FR_CZ_RX_MAC_FILTER_TBL0_STEP;
+	}
+
+	for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) {
+		table = &state->table[table_id];
+		if (table->size == 0)
+			continue;
+		table->used_bitmap = kcalloc(BITS_TO_LONGS(table->size),
+					     sizeof(unsigned long),
+					     GFP_KERNEL);
+		if (!table->used_bitmap)
+			goto fail;
+		table->spec = vzalloc(table->size * sizeof(*table->spec));
+		if (!table->spec)
+			goto fail;
+	}
+
+	return 0;
+
+fail:
+	efx_remove_filters(efx);
+	return -ENOMEM;
+}
+
+void efx_remove_filters(struct efx_nic *efx)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	enum efx_filter_table_id table_id;
+
+	for (table_id = 0; table_id < EFX_FILTER_TABLE_COUNT; table_id++) {
+		kfree(state->table[table_id].used_bitmap);
+		vfree(state->table[table_id].spec);
+	}
+#ifdef CONFIG_RFS_ACCEL
+	kfree(state->rps_flow_id);
+#endif
+	kfree(state);
+}
+
+#ifdef CONFIG_RFS_ACCEL
+
+int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
+		   u16 rxq_index, u32 flow_id)
+{
+	struct efx_nic *efx = netdev_priv(net_dev);
+	struct efx_channel *channel;
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_spec spec;
+	const struct iphdr *ip;
+	const __be16 *ports;
+	int nhoff;
+	int rc;
+
+	nhoff = skb_network_offset(skb);
+
+	if (skb->protocol != htons(ETH_P_IP))
+		return -EPROTONOSUPPORT;
+
+	/* RFS must validate the IP header length before calling us */
+	EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + sizeof(*ip));
+	ip = (const struct iphdr *)(skb->data + nhoff);
+	if (ip_is_fragment(ip))
+		return -EPROTONOSUPPORT;
+	EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + 4 * ip->ihl + 4);
+	ports = (const __be16 *)(skb->data + nhoff + 4 * ip->ihl);
+
+	efx_filter_init_rx(&spec, EFX_FILTER_PRI_HINT, 0, rxq_index);
+	rc = efx_filter_set_ipv4_full(&spec, ip->protocol,
+				      ip->daddr, ports[1], ip->saddr, ports[0]);
+	if (rc)
+		return rc;
+
+	rc = efx_filter_insert_filter(efx, &spec, true);
+	if (rc < 0)
+		return rc;
+
+	/* Remember this so we can check whether to expire the filter later */
+	state->rps_flow_id[rc] = flow_id;
+	channel = efx_get_channel(efx, skb_get_rx_queue(skb));
+	++channel->rfs_filters_added;
+
+	netif_info(efx, rx_status, efx->net_dev,
+		   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
+		   (ip->protocol == IPPROTO_TCP) ? "TCP" : "UDP",
+		   &ip->saddr, ntohs(ports[0]), &ip->daddr, ntohs(ports[1]),
+		   rxq_index, flow_id, rc);
+
+	return rc;
+}
+
+bool __efx_filter_rfs_expire(struct efx_nic *efx, unsigned quota)
+{
+	struct efx_filter_state *state = efx->filter_state;
+	struct efx_filter_table *table = &state->table[EFX_FILTER_TABLE_RX_IP];
+	unsigned mask = table->size - 1;
+	unsigned index;
+	unsigned stop;
+
+	if (!spin_trylock_bh(&state->lock))
+		return false;
+
+	index = state->rps_expire_index;
+	stop = (index + quota) & mask;
+
+	while (index != stop) {
+		if (test_bit(index, table->used_bitmap) &&
+		    table->spec[index].priority == EFX_FILTER_PRI_HINT &&
+		    rps_may_expire_flow(efx->net_dev,
+					table->spec[index].dmaq_id,
+					state->rps_flow_id[index], index)) {
+			netif_info(efx, rx_status, efx->net_dev,
+				   "expiring filter %d [flow %u]\n",
+				   index, state->rps_flow_id[index]);
+			efx_filter_table_clear_entry(efx, table, index);
+		}
+		index = (index + 1) & mask;
+	}
+
+	state->rps_expire_index = stop;
+	if (table->used == 0)
+		efx_filter_table_reset_search_depth(table);
+
+	spin_unlock_bh(&state->lock);
+	return true;
+}
+
+#endif /* CONFIG_RFS_ACCEL */