cxgb4: add support for offloading u32 filters

Add support for offloading u32 filter onto hardware.  Links are stored
in a jump table to perform necessary jumps to match TCP/UDP header.
When inserting rules in the linked bucket, the TCP/UDP match fields
in the corresponding entry of the jump table are appended to the filter
rule before insertion.  If a link is deleted, then all corresponding
filters associated with the link are also deleted.  Also enable
hardware tc offload as a supported feature.
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/Makefile

@@ -4,7 +4,7 @@
 
 obj-$(CONFIG_CHELSIO_T4) += cxgb4.o
 
-cxgb4-objs := cxgb4_main.o l2t.o t4_hw.o sge.o clip_tbl.o cxgb4_ethtool.o cxgb4_uld.o sched.o cxgb4_filter.o
+cxgb4-objs := cxgb4_main.o l2t.o t4_hw.o sge.o clip_tbl.o cxgb4_ethtool.o cxgb4_uld.o sched.o cxgb4_filter.o cxgb4_tc_u32.o
 cxgb4-$(CONFIG_CHELSIO_T4_DCB) +=  cxgb4_dcb.o
 cxgb4-$(CONFIG_CHELSIO_T4_FCOE) +=  cxgb4_fcoe.o
 cxgb4-$(CONFIG_DEBUG_FS) += cxgb4_debugfs.o

drivers/net/ethernet/chelsio/cxgb4/cxgb4.h

@@ -851,6 +851,9 @@ struct adapter {
 
 	spinlock_t stats_lock;
 	spinlock_t win0_lock ____cacheline_aligned_in_smp;
+
+	/* TC u32 offload */
+	struct cxgb4_tc_u32_table *tc_u32;
 };
 
 /* Support for "sched-class" command to allow a TX Scheduling Class to be

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -78,6 +78,7 @@
 #include "clip_tbl.h"
 #include "l2t.h"
 #include "sched.h"
+#include "cxgb4_tc_u32.h"
 
 char cxgb4_driver_name[] = KBUILD_MODNAME;
 
@@ -2711,6 +2712,35 @@ static int cxgb_set_tx_maxrate(struct net_device *dev, int index, u32 rate)
 	return err;
 }
 
+int cxgb_setup_tc(struct net_device *dev, u32 handle, __be16 proto,
+		  struct tc_to_netdev *tc)
+{
+	struct port_info *pi = netdev2pinfo(dev);
+	struct adapter *adap = netdev2adap(dev);
+
+	if (!(adap->flags & FULL_INIT_DONE)) {
+		dev_err(adap->pdev_dev,
+			"Failed to setup tc on port %d. Link Down?\n",
+			pi->port_id);
+		return -EINVAL;
+	}
+
+	if (TC_H_MAJ(handle) == TC_H_MAJ(TC_H_INGRESS) &&
+	    tc->type == TC_SETUP_CLSU32) {
+		switch (tc->cls_u32->command) {
+		case TC_CLSU32_NEW_KNODE:
+		case TC_CLSU32_REPLACE_KNODE:
+			return cxgb4_config_knode(dev, proto, tc->cls_u32);
+		case TC_CLSU32_DELETE_KNODE:
+			return cxgb4_delete_knode(dev, proto, tc->cls_u32);
+		default:
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return -EOPNOTSUPP;
+}
+
 static const struct net_device_ops cxgb4_netdev_ops = {
 	.ndo_open             = cxgb_open,
 	.ndo_stop             = cxgb_close,
@@ -2734,6 +2764,7 @@ static const struct net_device_ops cxgb4_netdev_ops = {
 	.ndo_busy_poll        = cxgb_busy_poll,
 #endif
 	.ndo_set_tx_maxrate   = cxgb_set_tx_maxrate,
+	.ndo_setup_tc         = cxgb_setup_tc,
 };
 
 #ifdef CONFIG_PCI_IOV
@@ -4406,6 +4437,7 @@ static void free_some_resources(struct adapter *adapter)
 	t4_free_mem(adapter->l2t);
 	t4_cleanup_sched(adapter);
 	t4_free_mem(adapter->tids.tid_tab);
+	cxgb4_cleanup_tc_u32(adapter);
 	kfree(adapter->sge.egr_map);
 	kfree(adapter->sge.ingr_map);
 	kfree(adapter->sge.starving_fl);
@@ -4750,7 +4782,8 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		netdev->hw_features = NETIF_F_SG | TSO_FLAGS |
 			NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
 			NETIF_F_RXCSUM | NETIF_F_RXHASH |
-			NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX;
+			NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX |
+			NETIF_F_HW_TC;
 		if (highdma)
 			netdev->hw_features |= NETIF_F_HIGHDMA;
 		netdev->features |= netdev->hw_features;
@@ -4838,6 +4871,12 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		dev_warn(&pdev->dev, "could not allocate TID table, "
 			 "continuing\n");
 		adapter->params.offload = 0;
+	} else {
+		adapter->tc_u32 = cxgb4_init_tc_u32(adapter,
+						    CXGB4_MAX_LINK_HANDLE);
+		if (!adapter->tc_u32)
+			dev_warn(&pdev->dev,
+				 "could not offload tc u32, continuing\n");
 	}
 
 	if (is_offload(adapter)) {

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.h

+/*
+ * This file is part of the Chelsio T4 Ethernet driver for Linux.
+ *
+ * Copyright (c) 2016 Chelsio Communications, Inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef __CXGB4_TC_U32_H
+#define __CXGB4_TC_U32_H
+
+#include <net/pkt_cls.h>
+
+#define CXGB4_MAX_LINK_HANDLE 32
+
+static inline bool can_tc_u32_offload(struct net_device *dev)
+{
+	struct adapter *adap = netdev2adap(dev);
+
+	return (dev->features & NETIF_F_HW_TC) && adap->tc_u32 ? true : false;
+}
+
+int cxgb4_config_knode(struct net_device *dev, __be16 protocol,
+		       struct tc_cls_u32_offload *cls);
+int cxgb4_delete_knode(struct net_device *dev, __be16 protocol,
+		       struct tc_cls_u32_offload *cls);
+
+void cxgb4_cleanup_tc_u32(struct adapter *adapter);
+struct cxgb4_tc_u32_table *cxgb4_init_tc_u32(struct adapter *adap,
+					     unsigned int size);
+#endif /* __CXGB4_TC_U32_H */

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32_parse.h

@@ -279,4 +279,16 @@ static const struct cxgb4_next_header cxgb4_ipv6_jumps[] = {
 	  .jump = cxgb4_udp_fields },
 	{ .jump = NULL }
 };
+
+struct cxgb4_link {
+	const struct cxgb4_match_field *match_field;  /* Next header */
+	struct ch_filter_specification fs; /* Match spec associated with link */
+	u32 link_handle;         /* Knode handle associated with the link */
+	unsigned long *tid_map;  /* Bitmap for filter tids */
+};
+
+struct cxgb4_tc_u32_table {
+	unsigned int size;          /* number of entries in table */
+	struct cxgb4_link table[0]; /* Jump table */
+};
 #endif /* __CXGB4_TC_U32_PARSE_H */