cxgb4: add support to create hash filters

Add support to create hash (exact-match) filters based on the value
of 'hash' field in ch_filter_specification.

Allocate SMT/L2T entries if DMAC-rewrite/SMAC-rewrite is requested.

Allocate CLIP entry in case of IPv6 filter.

Use cpl_act_open_req[6] to send hash filter create request to hw.
Also, the filter tuple is calculated as part of sending this request.

Hash-filter reply is processed on getting cpl_act_open_rpl.
In case of success, various bits/fields in filter-tcb are set per
filter requirement, such as enabling filter hitcnts, and/or various
header rewrite operations, such as VLAN-rewrite, NAT or
(L3/L4)-rewrite, and SMAC/DMAC-rewrite. In case of failure, clear the
filter entry and release any hw resources occupied by it.

The patch also moves the functions set_tcb_field, set_tcb_tflag and
configure_filter_smac towards beginning of file.

Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: Kumar Sanghvi

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

@@ -1050,6 +1050,7 @@ struct ch_filter_specification {
 	 * matching that doesn't exist as a (value, mask) tuple.
 	 */
 	uint32_t type:1;        /* 0 => IPv4, 1 => IPv6 */
+	u32 hash:1;		/* 0 => wild-card, 1 => exact-match */
 
 	/* Packet dispatch information.  Ingress packets which match the
 	 * filter rules will be dropped, passed to the host or switched back
@@ -1107,7 +1108,14 @@ enum {
 };
 
 enum {
-	NAT_MODE_ALL = 7,	/* NAT on entire 4-tuple */
+	NAT_MODE_NONE = 0,	/* No NAT performed */
+	NAT_MODE_DIP,		/* NAT on Dst IP */
+	NAT_MODE_DIP_DP,	/* NAT on Dst IP, Dst Port */
+	NAT_MODE_DIP_DP_SIP,	/* NAT on Dst IP, Dst Port and Src IP */
+	NAT_MODE_DIP_DP_SP,	/* NAT on Dst IP, Dst Port and Src Port */
+	NAT_MODE_SIP_SP,	/* NAT on Src IP and Src Port */
+	NAT_MODE_DIP_SIP_SP,	/* NAT on Dst IP, Src IP and Src Port */
+	NAT_MODE_ALL		/* NAT on entire 4-tuple */
 };
 
 /* Host shadow copy of ingress filter entry.  This is in host native format