linux/drivers/net/ethernet/sfc/tc.c

// SPDX-License-Identifier: GPL-2.0-only
/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2019 Solarflare Communications Inc.
 * Copyright 2020-2022 Xilinx 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 "tc.h"
#include "tc_bindings.h"
#include "mae.h"
#include "ef100_rep.h"
#include "efx.h"

#define EFX_EFV_PF	NULL
/* Look up the representor information (efv) for a device.
 * May return NULL for the PF (us), or an error pointer for a device that
 * isn't supported as a TC offload endpoint
 */
static struct efx_rep *efx_tc_flower_lookup_efv(struct efx_nic *efx,
						struct net_device *dev)
{
	struct efx_rep *efv;

	if (!dev)
		return ERR_PTR(-EOPNOTSUPP);
	/* Is it us (the PF)? */
	if (dev == efx->net_dev)
		return EFX_EFV_PF;
	/* Is it an efx vfrep at all? */
	if (dev->netdev_ops != &efx_ef100_rep_netdev_ops)
		return ERR_PTR(-EOPNOTSUPP);
	/* Is it ours?  We don't support TC rules that include another
	 * EF100's netdevices (not even on another port of the same NIC).
	 */
	efv = netdev_priv(dev);
	if (efv->parent != efx)
		return ERR_PTR(-EOPNOTSUPP);
	return efv;
}

static const struct rhashtable_params efx_tc_match_action_ht_params = {
	.key_len	= sizeof(unsigned long),
	.key_offset	= offsetof(struct efx_tc_flow_rule, cookie),
	.head_offset	= offsetof(struct efx_tc_flow_rule, linkage),
};

static void efx_tc_free_action_set(struct efx_nic *efx,
				   struct efx_tc_action_set *act, bool in_hw)
{
	/* Failure paths calling this on the 'running action' set in_hw=false,
	 * because if the alloc had succeeded we'd've put it in acts.list and
	 * not still have it in act.
	 */
	if (in_hw) {
		efx_mae_free_action_set(efx, act->fw_id);
		/* in_hw is true iff we are on an acts.list; make sure to
		 * remove ourselves from that list before we are freed.
		 */
		list_del(&act->list);
	}
	kfree(act);
}

static void efx_tc_free_action_set_list(struct efx_nic *efx,
					struct efx_tc_action_set_list *acts,
					bool in_hw)
{
	struct efx_tc_action_set *act, *next;

	/* Failure paths set in_hw=false, because usually the acts didn't get
	 * to efx_mae_alloc_action_set_list(); if they did, the failure tree
	 * has a separate efx_mae_free_action_set_list() before calling us.
	 */
	if (in_hw)
		efx_mae_free_action_set_list(efx, acts);
	/* Any act that's on the list will be in_hw even if the list isn't */
	list_for_each_entry_safe(act, next, &acts->list, list)
		efx_tc_free_action_set(efx, act, true);
	/* Don't kfree, as acts is embedded inside a struct efx_tc_flow_rule */
}

static void efx_tc_delete_rule(struct efx_nic *efx, struct efx_tc_flow_rule *rule)
{
	efx_mae_delete_rule(efx, rule->fw_id);

	/* Release entries in subsidiary tables */
	efx_tc_free_action_set_list(efx, &rule->acts, true);
	rule->fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
}

static void efx_tc_flow_free(void *ptr, void *arg)
{
	struct efx_tc_flow_rule *rule = ptr;
	struct efx_nic *efx = arg;

	netif_err(efx, drv, efx->net_dev,
		  "tc rule %lx still present at teardown, removing\n",
		  rule->cookie);

	efx_mae_delete_rule(efx, rule->fw_id);

	/* Release entries in subsidiary tables */
	efx_tc_free_action_set_list(efx, &rule->acts, true);

	kfree(rule);
}

static int efx_tc_flower_destroy(struct efx_nic *efx,
				 struct net_device *net_dev,
				 struct flow_cls_offload *tc)
{
	struct netlink_ext_ack *extack = tc->common.extack;
	struct efx_tc_flow_rule *rule;

	rule = rhashtable_lookup_fast(&efx->tc->match_action_ht, &tc->cookie,
				      efx_tc_match_action_ht_params);
	if (!rule) {
		/* Only log a message if we're the ingress device.  Otherwise
		 * it's a foreign filter and we might just not have been
		 * interested (e.g. we might not have been the egress device
		 * either).
		 */
		if (!IS_ERR(efx_tc_flower_lookup_efv(efx, net_dev)))
			netif_warn(efx, drv, efx->net_dev,
				   "Filter %lx not found to remove\n", tc->cookie);
		NL_SET_ERR_MSG_MOD(extack, "Flow cookie not found in offloaded rules");
		return -ENOENT;
	}

	/* Remove it from HW */
	efx_tc_delete_rule(efx, rule);
	/* Delete it from SW */
	rhashtable_remove_fast(&efx->tc->match_action_ht, &rule->linkage,
			       efx_tc_match_action_ht_params);
	netif_dbg(efx, drv, efx->net_dev, "Removed filter %lx\n", rule->cookie);
	kfree(rule);
	return 0;
}

int efx_tc_flower(struct efx_nic *efx, struct net_device *net_dev,
		  struct flow_cls_offload *tc, struct efx_rep *efv)
{
	int rc;

	if (!efx->tc)
		return -EOPNOTSUPP;

	mutex_lock(&efx->tc->mutex);
	switch (tc->command) {
	case FLOW_CLS_DESTROY:
		rc = efx_tc_flower_destroy(efx, net_dev, tc);
		break;
	default:
		rc = -EOPNOTSUPP;
		break;
	}
	mutex_unlock(&efx->tc->mutex);
	return rc;
}

static int efx_tc_configure_default_rule(struct efx_nic *efx, u32 ing_port,
					 u32 eg_port, struct efx_tc_flow_rule *rule)
{
	struct efx_tc_action_set_list *acts = &rule->acts;
	struct efx_tc_match *match = &rule->match;
	struct efx_tc_action_set *act;
	int rc;

	match->value.ingress_port = ing_port;
	match->mask.ingress_port = ~0;
	act = kzalloc(sizeof(*act), GFP_KERNEL);
	if (!act)
		return -ENOMEM;
	act->deliver = 1;
	act->dest_mport = eg_port;
	rc = efx_mae_alloc_action_set(efx, act);
	if (rc)
		goto fail1;
	EFX_WARN_ON_PARANOID(!list_empty(&acts->list));
	list_add_tail(&act->list, &acts->list);
	rc = efx_mae_alloc_action_set_list(efx, acts);
	if (rc)
		goto fail2;
	rc = efx_mae_insert_rule(efx, match, EFX_TC_PRIO_DFLT,
				 acts->fw_id, &rule->fw_id);
	if (rc)
		goto fail3;
	return 0;
fail3:
	efx_mae_free_action_set_list(efx, acts);
fail2:
	list_del(&act->list);
	efx_mae_free_action_set(efx, act->fw_id);
fail1:
	kfree(act);
	return rc;
}

static int efx_tc_configure_default_rule_pf(struct efx_nic *efx)
{
	struct efx_tc_flow_rule *rule = &efx->tc->dflt.pf;
	u32 ing_port, eg_port;

	efx_mae_mport_uplink(efx, &ing_port);
	efx_mae_mport_wire(efx, &eg_port);
	return efx_tc_configure_default_rule(efx, ing_port, eg_port, rule);
}

static int efx_tc_configure_default_rule_wire(struct efx_nic *efx)
{
	struct efx_tc_flow_rule *rule = &efx->tc->dflt.wire;
	u32 ing_port, eg_port;

	efx_mae_mport_wire(efx, &ing_port);
	efx_mae_mport_uplink(efx, &eg_port);
	return efx_tc_configure_default_rule(efx, ing_port, eg_port, rule);
}

int efx_tc_configure_default_rule_rep(struct efx_rep *efv)
{
	struct efx_tc_flow_rule *rule = &efv->dflt;
	struct efx_nic *efx = efv->parent;
	u32 ing_port, eg_port;

	efx_mae_mport_mport(efx, efv->mport, &ing_port);
	efx_mae_mport_mport(efx, efx->tc->reps_mport_id, &eg_port);
	return efx_tc_configure_default_rule(efx, ing_port, eg_port, rule);
}

void efx_tc_deconfigure_default_rule(struct efx_nic *efx,
				     struct efx_tc_flow_rule *rule)
{
	if (rule->fw_id != MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL)
		efx_tc_delete_rule(efx, rule);
	rule->fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
}

static int efx_tc_configure_rep_mport(struct efx_nic *efx)
{
	u32 rep_mport_label;
	int rc;

	rc = efx_mae_allocate_mport(efx, &efx->tc->reps_mport_id, &rep_mport_label);
	if (rc)
		return rc;
	pci_dbg(efx->pci_dev, "created rep mport 0x%08x (0x%04x)\n",
		efx->tc->reps_mport_id, rep_mport_label);
	/* Use mport *selector* as vport ID */
	efx_mae_mport_mport(efx, efx->tc->reps_mport_id,
			    &efx->tc->reps_mport_vport_id);
	return 0;
}

static void efx_tc_deconfigure_rep_mport(struct efx_nic *efx)
{
	efx_mae_free_mport(efx, efx->tc->reps_mport_id);
	efx->tc->reps_mport_id = MAE_MPORT_SELECTOR_NULL;
}

int efx_tc_insert_rep_filters(struct efx_nic *efx)
{
	struct efx_filter_spec promisc, allmulti;
	int rc;

	if (efx->type->is_vf)
		return 0;
	if (!efx->tc)
		return 0;
	efx_filter_init_rx(&promisc, EFX_FILTER_PRI_REQUIRED, 0, 0);
	efx_filter_set_uc_def(&promisc);
	efx_filter_set_vport_id(&promisc, efx->tc->reps_mport_vport_id);
	rc = efx_filter_insert_filter(efx, &promisc, false);
	if (rc < 0)
		return rc;
	efx->tc->reps_filter_uc = rc;
	efx_filter_init_rx(&allmulti, EFX_FILTER_PRI_REQUIRED, 0, 0);
	efx_filter_set_mc_def(&allmulti);
	efx_filter_set_vport_id(&allmulti, efx->tc->reps_mport_vport_id);
	rc = efx_filter_insert_filter(efx, &allmulti, false);
	if (rc < 0)
		return rc;
	efx->tc->reps_filter_mc = rc;
	return 0;
}

void efx_tc_remove_rep_filters(struct efx_nic *efx)
{
	if (efx->type->is_vf)
		return;
	if (!efx->tc)
		return;
	if (efx->tc->reps_filter_mc >= 0)
		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, efx->tc->reps_filter_mc);
	efx->tc->reps_filter_mc = -1;
	if (efx->tc->reps_filter_uc >= 0)
		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED, efx->tc->reps_filter_uc);
	efx->tc->reps_filter_uc = -1;
}

int efx_init_tc(struct efx_nic *efx)
{
	int rc;

	rc = efx_tc_configure_default_rule_pf(efx);
	if (rc)
		return rc;
	rc = efx_tc_configure_default_rule_wire(efx);
	if (rc)
		return rc;
	rc = efx_tc_configure_rep_mport(efx);
	if (rc)
		return rc;
	efx->tc->up = true;
	rc = flow_indr_dev_register(efx_tc_indr_setup_cb, efx);
	if (rc)
		return rc;
	return 0;
}

void efx_fini_tc(struct efx_nic *efx)
{
	/* We can get called even if efx_init_struct_tc() failed */
	if (!efx->tc)
		return;
	if (efx->tc->up)
		flow_indr_dev_unregister(efx_tc_indr_setup_cb, efx, efx_tc_block_unbind);
	efx_tc_deconfigure_rep_mport(efx);
	efx_tc_deconfigure_default_rule(efx, &efx->tc->dflt.pf);
	efx_tc_deconfigure_default_rule(efx, &efx->tc->dflt.wire);
	efx->tc->up = false;
}

int efx_init_struct_tc(struct efx_nic *efx)
{
	int rc;

	if (efx->type->is_vf)
		return 0;

	efx->tc = kzalloc(sizeof(*efx->tc), GFP_KERNEL);
	if (!efx->tc)
		return -ENOMEM;
	INIT_LIST_HEAD(&efx->tc->block_list);

	mutex_init(&efx->tc->mutex);
	rc = rhashtable_init(&efx->tc->match_action_ht, &efx_tc_match_action_ht_params);
	if (rc < 0)
		goto fail_match_action_ht;
	efx->tc->reps_filter_uc = -1;
	efx->tc->reps_filter_mc = -1;
	INIT_LIST_HEAD(&efx->tc->dflt.pf.acts.list);
	efx->tc->dflt.pf.fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
	INIT_LIST_HEAD(&efx->tc->dflt.wire.acts.list);
	efx->tc->dflt.wire.fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
	return 0;
fail_match_action_ht:
	mutex_destroy(&efx->tc->mutex);
	kfree(efx->tc);
	efx->tc = NULL;
	return rc;
}

void efx_fini_struct_tc(struct efx_nic *efx)
{
	if (!efx->tc)
		return;

	mutex_lock(&efx->tc->mutex);
	EFX_WARN_ON_PARANOID(efx->tc->dflt.pf.fw_id !=
			     MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL);
	EFX_WARN_ON_PARANOID(efx->tc->dflt.wire.fw_id !=
			     MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL);
	rhashtable_free_and_destroy(&efx->tc->match_action_ht, efx_tc_flow_free,
				    efx);
	mutex_unlock(&efx->tc->mutex);
	mutex_destroy(&efx->tc->mutex);
	kfree(efx->tc);
	efx->tc = NULL;
}