enic: devcmd for adding IP 5 tuple hardware filters

This patch adds interface to add and delete IP 5 tuple filter. This interface
is used by Accelerated RFS code to steer a flow to corresponding receive
queue.

As of now adaptor supports only ipv4 + tcp/udp packet steering.
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cisco/enic/Makefile

@@ -2,5 +2,5 @@ obj-$(CONFIG_ENIC) := enic.o
 
 enic-y := enic_main.o vnic_cq.o vnic_intr.o vnic_wq.o \
 	enic_res.o enic_dev.o enic_pp.o vnic_dev.o vnic_rq.o vnic_vic.o \
-	enic_ethtool.o enic_api.o
+	enic_ethtool.o enic_api.o enic_clsf.o
 

drivers/net/ethernet/cisco/enic/enic_clsf.c

+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/if_link.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <net/flow_keys.h>
+#include "enic_res.h"
+#include "enic_clsf.h"
+
+/* enic_addfltr_5t - Add ipv4 5tuple filter
+ *	@enic: enic struct of vnic
+ *	@keys: flow_keys of ipv4 5tuple
+ *	@rq: rq number to steer to
+ *
+ * This function returns filter_id(hardware_id) of the filter
+ * added. In case of error it returns an negative number.
+ */
+int enic_addfltr_5t(struct enic *enic, struct flow_keys *keys, u16 rq)
+{
+	int res;
+	struct filter data;
+
+	switch (keys->ip_proto) {
+	case IPPROTO_TCP:
+		data.u.ipv4.protocol = PROTO_TCP;
+		break;
+	case IPPROTO_UDP:
+		data.u.ipv4.protocol = PROTO_UDP;
+		break;
+	default:
+		return -EPROTONOSUPPORT;
+	};
+	data.type = FILTER_IPV4_5TUPLE;
+	data.u.ipv4.src_addr = ntohl(keys->src);
+	data.u.ipv4.dst_addr = ntohl(keys->dst);
+	data.u.ipv4.src_port = ntohs(keys->port16[0]);
+	data.u.ipv4.dst_port = ntohs(keys->port16[1]);
+	data.u.ipv4.flags = FILTER_FIELDS_IPV4_5TUPLE;
+
+	spin_lock_bh(&enic->devcmd_lock);
+	res = vnic_dev_classifier(enic->vdev, CLSF_ADD, &rq, &data);
+	spin_unlock_bh(&enic->devcmd_lock);
+	res = (res == 0) ? rq : res;
+
+	return res;
+}
+
+/* enic_delfltr - Delete clsf filter
+ *	@enic: enic struct of vnic
+ *	@filter_id: filter_is(hardware_id) of filter to be deleted
+ *
+ * This function returns zero in case of success, negative number incase of
+ * error.
+ */
+int enic_delfltr(struct enic *enic, u16 filter_id)
+{
+	int ret;
+
+	spin_lock_bh(&enic->devcmd_lock);
+	ret = vnic_dev_classifier(enic->vdev, CLSF_DEL, &filter_id, NULL);
+	spin_unlock_bh(&enic->devcmd_lock);
+
+	return ret;
+}

drivers/net/ethernet/cisco/enic/enic_clsf.h

+#ifndef _ENIC_CLSF_H_
+#define _ENIC_CLSF_H_
+
+#include "vnic_dev.h"
+#include "enic.h"
+
+int enic_addfltr_5t(struct enic *enic, struct flow_keys *keys, u16 rq);
+int enic_delfltr(struct enic *enic, u16 filter_id);
+
+#endif /* _ENIC_CLSF_H_ */

drivers/net/ethernet/cisco/enic/vnic_dev.c

@@ -1048,3 +1048,64 @@ int vnic_dev_set_mac_addr(struct vnic_dev *vdev, u8 *mac_addr)
 
 	return vnic_dev_cmd(vdev, CMD_SET_MAC_ADDR, &a0, &a1, wait);
 }
+
+/* vnic_dev_classifier: Add/Delete classifier entries
+ * @vdev: vdev of the device
+ * @cmd: CLSF_ADD for Add filter
+ *	 CLSF_DEL for Delete filter
+ * @entry: In case of ADD filter, the caller passes the RQ number in this
+ *	   variable.
+ *
+ *	   This function stores the filter_id returned by the firmware in the
+ *	   same variable before return;
+ *
+ *	   In case of DEL filter, the caller passes the RQ number. Return
+ *	   value is irrelevant.
+ * @data: filter data
+ */
+int vnic_dev_classifier(struct vnic_dev *vdev, u8 cmd, u16 *entry,
+			struct filter *data)
+{
+	u64 a0, a1;
+	int wait = 1000;
+	dma_addr_t tlv_pa;
+	int ret = -EINVAL;
+	struct filter_tlv *tlv, *tlv_va;
+	struct filter_action *action;
+	u64 tlv_size;
+
+	if (cmd == CLSF_ADD) {
+		tlv_size = sizeof(struct filter) +
+			   sizeof(struct filter_action) +
+			   2 * sizeof(struct filter_tlv);
+		tlv_va = pci_alloc_consistent(vdev->pdev, tlv_size, &tlv_pa);
+		if (!tlv_va)
+			return -ENOMEM;
+		tlv = tlv_va;
+		a0 = tlv_pa;
+		a1 = tlv_size;
+		memset(tlv, 0, tlv_size);
+		tlv->type = CLSF_TLV_FILTER;
+		tlv->length = sizeof(struct filter);
+		*(struct filter *)&tlv->val = *data;
+
+		tlv = (struct filter_tlv *)((char *)tlv +
+					    sizeof(struct filter_tlv) +
+					    sizeof(struct filter));
+
+		tlv->type = CLSF_TLV_ACTION;
+		tlv->length = sizeof(struct filter_action);
+		action = (struct filter_action *)&tlv->val;
+		action->type = FILTER_ACTION_RQ_STEERING;
+		action->u.rq_idx = *entry;
+
+		ret = vnic_dev_cmd(vdev, CMD_ADD_FILTER, &a0, &a1, wait);
+		*entry = (u16)a0;
+		pci_free_consistent(vdev->pdev, tlv_size, tlv_va, tlv_pa);
+	} else if (cmd == CLSF_DEL) {
+		a0 = *entry;
+		ret = vnic_dev_cmd(vdev, CMD_DEL_FILTER, &a0, &a1, wait);
+	}
+
+	return ret;
+}

drivers/net/ethernet/cisco/enic/vnic_dev.h

@@ -133,5 +133,7 @@ int vnic_dev_enable2(struct vnic_dev *vdev, int active);
 int vnic_dev_enable2_done(struct vnic_dev *vdev, int *status);
 int vnic_dev_deinit_done(struct vnic_dev *vdev, int *status);
 int vnic_dev_set_mac_addr(struct vnic_dev *vdev, u8 *mac_addr);
+int vnic_dev_classifier(struct vnic_dev *vdev, u8 cmd, u16 *entry,
+			struct filter *data);
 
 #endif /* _VNIC_DEV_H_ */

drivers/net/ethernet/cisco/enic/vnic_devcmd.h

@@ -603,6 +603,11 @@ struct filter_tlv {
 	u_int32_t val[0];
 };
 
+enum {
+	CLSF_ADD = 0,
+	CLSF_DEL = 1,
+};
+
 /*
  * Writing cmd register causes STAT_BUSY to get set in status register.
  * When cmd completes, STAT_BUSY will be cleared.