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From: Vadym Kochan <vadym.kochan@plvision.eu>
To: "David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	netdev@vger.kernel.org, Andrew Lunn <andrew@lunn.ch>,
	Vladimir Oltean <olteanv@gmail.com>
Cc: Vadym Kochan <vadym.kochan@plvision.eu>,
	Taras Chornyi <tchornyi@marvell.com>,
	linux-kernel@vger.kernel.org,
	Mickey Rachamim <mickeyr@marvell.com>,
	Serhiy Boiko <serhiy.boiko@plvision.eu>,
	Volodymyr Mytnyk <vmytnyk@marvell.com>,
	Vadym Kochan <vkochan@marvell.com>
Subject: [PATCH net-next 2/2] net: marvell: prestera: Add matchall support
Date: Tue, 15 Jun 2021 15:54:44 +0300	[thread overview]
Message-ID: <20210615125444.31538-3-vadym.kochan@plvision.eu> (raw)
In-Reply-To: <20210615125444.31538-1-vadym.kochan@plvision.eu>

From: Serhiy Boiko <serhiy.boiko@plvision.eu>

- Introduce matchall filter support
- Add SPAN API to configure port mirroring.
- Add tc mirror action.

At this moment, only mirror (egress) action is supported.

Example:
    tc filter ... action mirred egress mirror dev DEV

Co-developed-by: Volodymyr Mytnyk <vmytnyk@marvell.com>
Signed-off-by: Volodymyr Mytnyk <vmytnyk@marvell.com>
Signed-off-by: Serhiy Boiko <serhiy.boiko@plvision.eu>
Signed-off-by: Vadym Kochan <vkochan@marvell.com>
---
 .../net/ethernet/marvell/prestera/Makefile    |   2 +-
 .../net/ethernet/marvell/prestera/prestera.h  |   2 +
 .../ethernet/marvell/prestera/prestera_acl.c  |   2 +
 .../ethernet/marvell/prestera/prestera_acl.h  |   3 +-
 .../ethernet/marvell/prestera/prestera_flow.c |  19 ++
 .../ethernet/marvell/prestera/prestera_hw.c   |  69 +++++
 .../ethernet/marvell/prestera/prestera_hw.h   |   6 +
 .../ethernet/marvell/prestera/prestera_main.c |   8 +
 .../ethernet/marvell/prestera/prestera_span.c | 245 ++++++++++++++++++
 .../ethernet/marvell/prestera/prestera_span.h |  20 ++
 10 files changed, 374 insertions(+), 2 deletions(-)
 create mode 100644 drivers/net/ethernet/marvell/prestera/prestera_span.c
 create mode 100644 drivers/net/ethernet/marvell/prestera/prestera_span.h

diff --git a/drivers/net/ethernet/marvell/prestera/Makefile b/drivers/net/ethernet/marvell/prestera/Makefile
index 42327c4afdbf..0609df8b913d 100644
--- a/drivers/net/ethernet/marvell/prestera/Makefile
+++ b/drivers/net/ethernet/marvell/prestera/Makefile
@@ -3,6 +3,6 @@ obj-$(CONFIG_PRESTERA)	+= prestera.o
 prestera-objs		:= prestera_main.o prestera_hw.o prestera_dsa.o \
 			   prestera_rxtx.o prestera_devlink.o prestera_ethtool.o \
 			   prestera_switchdev.o prestera_acl.o prestera_flow.o \
-			   prestera_flower.o
+			   prestera_flower.o prestera_span.o
 
 obj-$(CONFIG_PRESTERA_PCI)	+= prestera_pci.o
diff --git a/drivers/net/ethernet/marvell/prestera/prestera.h b/drivers/net/ethernet/marvell/prestera/prestera.h
index bbbe780d0886..f18fe664b373 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera.h
@@ -172,6 +172,7 @@ struct prestera_event {
 };
 
 struct prestera_switchdev;
+struct prestera_span;
 struct prestera_rxtx;
 struct prestera_trap_data;
 struct prestera_acl;
@@ -181,6 +182,7 @@ struct prestera_switch {
 	struct prestera_switchdev *swdev;
 	struct prestera_rxtx *rxtx;
 	struct prestera_acl *acl;
+	struct prestera_span *span;
 	struct list_head event_handlers;
 	struct notifier_block netdev_nb;
 	struct prestera_trap_data *trap_data;
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_acl.c b/drivers/net/ethernet/marvell/prestera/prestera_acl.c
index 817f78b1e90c..5165ac96a70e 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_acl.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_acl.c
@@ -6,6 +6,7 @@
 #include "prestera.h"
 #include "prestera_hw.h"
 #include "prestera_acl.h"
+#include "prestera_span.h"
 
 struct prestera_acl {
 	struct prestera_switch *sw;
@@ -149,6 +150,7 @@ int prestera_acl_block_bind(struct prestera_flow_block *block,
 	binding = kzalloc(sizeof(*binding), GFP_KERNEL);
 	if (!binding)
 		return -ENOMEM;
+	binding->span_id = PRESTERA_SPAN_INVALID_ID;
 	binding->port = port;
 
 	err = prestera_hw_acl_port_bind(port, block->ruleset->id);
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_acl.h b/drivers/net/ethernet/marvell/prestera/prestera_acl.h
index 935c79a26036..2f129eb55547 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_acl.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera_acl.h
@@ -28,14 +28,15 @@ enum prestera_acl_rule_action {
 	PRESTERA_ACL_RULE_ACTION_TRAP
 };
 
-struct prestera_switch;
 struct prestera_port;
+struct prestera_switch;
 struct prestera_acl_rule;
 struct prestera_acl_ruleset;
 
 struct prestera_flow_block_binding {
 	struct list_head list;
 	struct prestera_port *port;
+	int span_id;
 };
 
 struct prestera_flow_block {
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_flow.c b/drivers/net/ethernet/marvell/prestera/prestera_flow.c
index b818dd871512..b350082a1815 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_flow.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_flow.c
@@ -7,10 +7,25 @@
 #include "prestera.h"
 #include "prestera_acl.h"
 #include "prestera_flow.h"
+#include "prestera_span.h"
 #include "prestera_flower.h"
 
 static LIST_HEAD(prestera_block_cb_list);
 
+static int prestera_flow_block_mall_cb(struct prestera_flow_block *block,
+				       struct tc_cls_matchall_offload *f)
+{
+	switch (f->command) {
+	case TC_CLSMATCHALL_REPLACE:
+		return prestera_span_replace(block, f);
+	case TC_CLSMATCHALL_DESTROY:
+		prestera_span_destroy(block);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
 static int prestera_flow_block_flower_cb(struct prestera_flow_block *block,
 					 struct flow_cls_offload *f)
 {
@@ -41,6 +56,8 @@ static int prestera_flow_block_cb(enum tc_setup_type type,
 	switch (type) {
 	case TC_SETUP_CLSFLOWER:
 		return prestera_flow_block_flower_cb(block, type_data);
+	case TC_SETUP_CLSMATCHALL:
+		return prestera_flow_block_mall_cb(block, type_data);
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -163,6 +180,8 @@ static void prestera_setup_flow_block_unbind(struct prestera_port *port,
 	if (!tc_can_offload(port->dev))
 		prestera_acl_block_disable_dec(block);
 
+	prestera_span_destroy(block);
+
 	err = prestera_acl_block_unbind(block, port);
 	if (err)
 		goto error;
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_hw.c b/drivers/net/ethernet/marvell/prestera/prestera_hw.c
index 42b8d9f56468..c1297859e471 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_hw.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_hw.c
@@ -56,6 +56,11 @@ enum prestera_cmd_type_t {
 
 	PRESTERA_CMD_TYPE_STP_PORT_SET = 0x1000,
 
+	PRESTERA_CMD_TYPE_SPAN_GET = 0x1100,
+	PRESTERA_CMD_TYPE_SPAN_BIND = 0x1101,
+	PRESTERA_CMD_TYPE_SPAN_UNBIND = 0x1102,
+	PRESTERA_CMD_TYPE_SPAN_RELEASE = 0x1103,
+
 	PRESTERA_CMD_TYPE_CPU_CODE_COUNTERS_GET = 0x2000,
 
 	PRESTERA_CMD_TYPE_ACK = 0x10000,
@@ -377,6 +382,18 @@ struct prestera_msg_acl_ruleset_resp {
 	u16 id;
 };
 
+struct prestera_msg_span_req {
+	struct prestera_msg_cmd cmd;
+	u32 port;
+	u32 dev;
+	u8 id;
+} __packed __aligned(4);
+
+struct prestera_msg_span_resp {
+	struct prestera_msg_ret ret;
+	u8 id;
+} __packed __aligned(4);
+
 struct prestera_msg_stp_req {
 	struct prestera_msg_cmd cmd;
 	u32 port;
@@ -1055,6 +1072,58 @@ int prestera_hw_acl_port_unbind(const struct prestera_port *port,
 			    &req.cmd, sizeof(req));
 }
 
+int prestera_hw_span_get(const struct prestera_port *port, u8 *span_id)
+{
+	struct prestera_msg_span_resp resp;
+	struct prestera_msg_span_req req = {
+		.port = port->hw_id,
+		.dev = port->dev_id,
+	};
+	int err;
+
+	err = prestera_cmd_ret(port->sw, PRESTERA_CMD_TYPE_SPAN_GET,
+			       &req.cmd, sizeof(req), &resp.ret, sizeof(resp));
+	if (err)
+		return err;
+
+	*span_id = resp.id;
+
+	return 0;
+}
+
+int prestera_hw_span_bind(const struct prestera_port *port, u8 span_id)
+{
+	struct prestera_msg_span_req req = {
+		.port = port->hw_id,
+		.dev = port->dev_id,
+		.id = span_id,
+	};
+
+	return prestera_cmd(port->sw, PRESTERA_CMD_TYPE_SPAN_BIND,
+			    &req.cmd, sizeof(req));
+}
+
+int prestera_hw_span_unbind(const struct prestera_port *port)
+{
+	struct prestera_msg_span_req req = {
+		.port = port->hw_id,
+		.dev = port->dev_id,
+	};
+
+	return prestera_cmd(port->sw, PRESTERA_CMD_TYPE_SPAN_UNBIND,
+			    &req.cmd, sizeof(req));
+}
+
+int prestera_hw_span_release(struct prestera_switch *sw, u8 span_id)
+{
+	struct prestera_msg_span_req req = {
+		.id = span_id
+	};
+
+	return prestera_cmd(sw, PRESTERA_CMD_TYPE_SPAN_RELEASE,
+			    &req.cmd, sizeof(req));
+}
+
 int prestera_hw_port_type_get(const struct prestera_port *port, u8 *type)
 {
 	struct prestera_msg_port_attr_req req = {
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_hw.h b/drivers/net/ethernet/marvell/prestera/prestera_hw.h
index c01d376574d2..546d5fd8240d 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_hw.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera_hw.h
@@ -188,6 +188,12 @@ int prestera_hw_acl_port_bind(const struct prestera_port *port,
 int prestera_hw_acl_port_unbind(const struct prestera_port *port,
 				u16 ruleset_id);
 
+/* SPAN API */
+int prestera_hw_span_get(const struct prestera_port *port, u8 *span_id);
+int prestera_hw_span_bind(const struct prestera_port *port, u8 span_id);
+int prestera_hw_span_unbind(const struct prestera_port *port);
+int prestera_hw_span_release(struct prestera_switch *sw, u8 span_id);
+
 /* Event handlers */
 int prestera_hw_event_handler_register(struct prestera_switch *sw,
 				       enum prestera_event_type type,
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c
index ea683b5a8a2e..d2a738da368a 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_main.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c
@@ -14,6 +14,7 @@
 #include "prestera_hw.h"
 #include "prestera_acl.h"
 #include "prestera_flow.h"
+#include "prestera_span.h"
 #include "prestera_rxtx.h"
 #include "prestera_devlink.h"
 #include "prestera_ethtool.h"
@@ -909,6 +910,10 @@ static int prestera_switch_init(struct prestera_switch *sw)
 	if (err)
 		goto err_acl_init;
 
+	err = prestera_span_init(sw);
+	if (err)
+		goto err_span_init;
+
 	err = prestera_devlink_register(sw);
 	if (err)
 		goto err_dl_register;
@@ -928,6 +933,8 @@ static int prestera_switch_init(struct prestera_switch *sw)
 err_lag_init:
 	prestera_devlink_unregister(sw);
 err_dl_register:
+	prestera_span_fini(sw);
+err_span_init:
 	prestera_acl_fini(sw);
 err_acl_init:
 	prestera_event_handlers_unregister(sw);
@@ -947,6 +954,7 @@ static void prestera_switch_fini(struct prestera_switch *sw)
 	prestera_destroy_ports(sw);
 	prestera_lag_fini(sw);
 	prestera_devlink_unregister(sw);
+	prestera_span_fini(sw);
 	prestera_acl_fini(sw);
 	prestera_event_handlers_unregister(sw);
 	prestera_rxtx_switch_fini(sw);
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_span.c b/drivers/net/ethernet/marvell/prestera/prestera_span.c
new file mode 100644
index 000000000000..d399e47fb429
--- /dev/null
+++ b/drivers/net/ethernet/marvell/prestera/prestera_span.c
@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/* Copyright (c) 2020 Marvell International Ltd. All rights reserved */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+
+#include "prestera.h"
+#include "prestera_hw.h"
+#include "prestera_acl.h"
+#include "prestera_span.h"
+
+struct prestera_span_entry {
+	struct list_head list;
+	struct prestera_port *port;
+	refcount_t ref_count;
+	u8 id;
+};
+
+struct prestera_span {
+	struct prestera_switch *sw;
+	struct list_head entries;
+};
+
+static struct prestera_span_entry *
+prestera_span_entry_create(struct prestera_port *port, u8 span_id)
+{
+	struct prestera_span_entry *entry;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return ERR_PTR(-ENOMEM);
+
+	refcount_set(&entry->ref_count, 1);
+	entry->port = port;
+	entry->id = span_id;
+	list_add_tail(&entry->list, &port->sw->span->entries);
+
+	return entry;
+}
+
+static void prestera_span_entry_del(struct prestera_span_entry *entry)
+{
+	list_del(&entry->list);
+	kfree(entry);
+}
+
+static struct prestera_span_entry *
+prestera_span_entry_find_by_id(struct prestera_span *span, u8 span_id)
+{
+	struct prestera_span_entry *entry;
+
+	list_for_each_entry(entry, &span->entries, list) {
+		if (entry->id == span_id)
+			return entry;
+	}
+
+	return NULL;
+}
+
+static struct prestera_span_entry *
+prestera_span_entry_find_by_port(struct prestera_span *span,
+				 struct prestera_port *port)
+{
+	struct prestera_span_entry *entry;
+
+	list_for_each_entry(entry, &span->entries, list) {
+		if (entry->port == port)
+			return entry;
+	}
+
+	return NULL;
+}
+
+static int prestera_span_get(struct prestera_port *port, u8 *span_id)
+{
+	u8 new_span_id;
+	struct prestera_switch *sw = port->sw;
+	struct prestera_span_entry *entry;
+	int err;
+
+	entry = prestera_span_entry_find_by_port(sw->span, port);
+	if (entry) {
+		refcount_inc(&entry->ref_count);
+		*span_id = entry->id;
+		return 0;
+	}
+
+	err = prestera_hw_span_get(port, &new_span_id);
+	if (err)
+		return err;
+
+	entry = prestera_span_entry_create(port, new_span_id);
+	if (IS_ERR(entry)) {
+		prestera_hw_span_release(sw, new_span_id);
+		return PTR_ERR(entry);
+	}
+
+	*span_id = new_span_id;
+	return 0;
+}
+
+static int prestera_span_put(struct prestera_switch *sw, u8 span_id)
+{
+	struct prestera_span_entry *entry;
+	int err;
+
+	entry = prestera_span_entry_find_by_id(sw->span, span_id);
+	if (!entry)
+		return false;
+
+	if (!refcount_dec_and_test(&entry->ref_count))
+		return 0;
+
+	err = prestera_hw_span_release(sw, span_id);
+	if (err)
+		return err;
+
+	prestera_span_entry_del(entry);
+	return 0;
+}
+
+static int prestera_span_rule_add(struct prestera_flow_block_binding *binding,
+				  struct prestera_port *to_port)
+{
+	int err;
+	u8 span_id;
+	struct prestera_switch *sw = binding->port->sw;
+
+	if (binding->span_id != PRESTERA_SPAN_INVALID_ID)
+		/* port already in mirroring */
+		return -EEXIST;
+
+	err = prestera_span_get(to_port, &span_id);
+	if (err)
+		return err;
+
+	err = prestera_hw_span_bind(binding->port, span_id);
+	if (err) {
+		prestera_span_put(sw, span_id);
+		return err;
+	}
+
+	binding->span_id = span_id;
+	return 0;
+}
+
+static int prestera_span_rule_del(struct prestera_flow_block_binding *binding)
+{
+	int err;
+
+	err = prestera_hw_span_unbind(binding->port);
+	if (err)
+		return err;
+
+	err = prestera_span_put(binding->port->sw, binding->span_id);
+	if (err)
+		return err;
+
+	binding->span_id = PRESTERA_SPAN_INVALID_ID;
+	return 0;
+}
+
+int prestera_span_replace(struct prestera_flow_block *block,
+			  struct tc_cls_matchall_offload *f)
+{
+	struct prestera_flow_block_binding *binding;
+	__be16 protocol = f->common.protocol;
+	struct flow_action_entry *act;
+	struct prestera_port *port;
+	int err;
+
+	if (!flow_offload_has_one_action(&f->rule->action)) {
+		NL_SET_ERR_MSG(f->common.extack,
+			       "Only singular actions are supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (f->common.chain_index) {
+		NL_SET_ERR_MSG(f->common.extack, "Only chain 0 is supported");
+		return -EOPNOTSUPP;
+	}
+
+	act = &f->rule->action.entries[0];
+
+	if (act->id != FLOW_ACTION_MIRRED)
+		return -EOPNOTSUPP;
+
+	if (protocol != htons(ETH_P_ALL))
+		return -EOPNOTSUPP;
+
+	/* TODO: add prio check */
+
+	if (!prestera_netdev_check(act->dev)) {
+		NL_SET_ERR_MSG(f->common.extack,
+			       "Only switchdev port is supported");
+		return -EINVAL;
+	}
+
+	port = netdev_priv(act->dev);
+	list_for_each_entry(binding, &block->binding_list, list) {
+		err = prestera_span_rule_add(binding, port);
+		if (err)
+			goto rollback;
+	}
+	return 0;
+
+rollback:
+	list_for_each_entry_continue_reverse(binding,
+					     &block->binding_list, list)
+		prestera_span_rule_del(binding);
+	return err;
+}
+
+void prestera_span_destroy(struct prestera_flow_block *block)
+{
+	struct prestera_flow_block_binding *binding;
+
+	list_for_each_entry(binding, &block->binding_list, list)
+		prestera_span_rule_del(binding);
+}
+
+int prestera_span_init(struct prestera_switch *sw)
+{
+	struct prestera_span *span;
+
+	span = kzalloc(sizeof(*span), GFP_KERNEL);
+	if (!span)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&span->entries);
+
+	sw->span = span;
+	span->sw = sw;
+
+	return 0;
+}
+
+void prestera_span_fini(struct prestera_switch *sw)
+{
+	struct prestera_span *span = sw->span;
+
+	WARN_ON(!list_empty(&span->entries));
+	kfree(span);
+}
+
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_span.h b/drivers/net/ethernet/marvell/prestera/prestera_span.h
new file mode 100644
index 000000000000..f0644521f78a
--- /dev/null
+++ b/drivers/net/ethernet/marvell/prestera/prestera_span.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/* Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved. */
+
+#ifndef _PRESTERA_SPAN_H_
+#define _PRESTERA_SPAN_H_
+
+#include <net/pkt_cls.h>
+
+#define PRESTERA_SPAN_INVALID_ID -1
+
+struct prestera_switch;
+struct prestera_flow_block;
+
+int prestera_span_init(struct prestera_switch *sw);
+void prestera_span_fini(struct prestera_switch *sw);
+int prestera_span_replace(struct prestera_flow_block *block,
+			  struct tc_cls_matchall_offload *f);
+void prestera_span_destroy(struct prestera_flow_block *block);
+
+#endif /* _PRESTERA_SPAN_H_ */
-- 
2.17.1


  parent reply	other threads:[~2021-06-15 12:55 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-15 12:54 [PATCH net-next 0/2] Marvell Prestera add flower and match all support Vadym Kochan
2021-06-15 12:54 ` [PATCH net-next 1/2] net: marvell: Implement TC flower offload Vadym Kochan
2021-06-16  0:54   ` Vladimir Oltean
2021-06-16 13:04     ` Vadym Kochan
2021-06-16 13:07       ` Vladimir Oltean
2021-06-15 12:54 ` Vadym Kochan [this message]
2021-06-16  1:07   ` [PATCH net-next 2/2] net: marvell: prestera: Add matchall support Vladimir Oltean
2021-06-15 18:37 ` [PATCH net-next 0/2] Marvell Prestera add flower and match all support David Miller

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