IB/mlx4: Add support for RSS QP

Add support to work with a RSS QP by using an indirection table object
upon QP creation. Other related QP verbs (e.g. modify/destroy/query) were
updated as well for that QP mode.

Notes:
- The RX hash properties are supplied as driver private data.
- The RSS QP port is used on the associated WQs in its indirection
  table. Applying different ports during WQ life time is not allowed.
- The expected RSS QP flow is: create, modify(RST->INIT),
  modify(RST->RTR), destroy.

Signed-off-by: Guy Levi <guyle@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx4/mlx4_ib.h

@@ -46,6 +46,7 @@
 
 #include <linux/mlx4/device.h>
 #include <linux/mlx4/doorbell.h>
+#include <linux/mlx4/qp.h>
 
 #define MLX4_IB_DRV_NAME	"mlx4_ib"
 
@@ -299,6 +300,12 @@ struct mlx4_wqn_range {
 	struct list_head	list;
 };
 
+struct mlx4_ib_rss {
+	unsigned int		base_qpn_tbl_sz;
+	u8			flags;
+	u8			rss_key[MLX4_EN_RSS_KEY_SIZE];
+};
+
 struct mlx4_ib_qp {
 	union {
 		struct ib_qp	ibqp;
@@ -345,6 +352,7 @@ struct mlx4_ib_qp {
 	struct mlx4_wqn_range	*wqn_range;
 	/* Number of RSS QP parents that uses this WQ */
 	u32			rss_usecnt;
+	struct mlx4_ib_rss	*rss_ctx;
 };
 
 struct mlx4_ib_srq {