RDS/IW: Convert to new memory registration API

Get rid of fast_reg page list and its construction.
Instead, just pass the RDS sg list to ib_map_mr_sg
and post the new ib_reg_wr.

This is done both for server IW RDMA_READ registration
and the client remote key registration.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/net/rds/iw.h b/net/rds/iw.h
index fe858e5..5af01d1 100644
--- a/net/rds/iw.h
+++ b/net/rds/iw.h
@@ -74,13 +74,12 @@
 	struct rm_rdma_op	*s_op;
 	struct rds_iw_mapping	*s_mapping;
 	struct ib_mr		*s_mr;
-	struct ib_fast_reg_page_list *s_page_list;
 	unsigned char		s_remap_count;
 
 	union {
 		struct ib_send_wr	s_send_wr;
 		struct ib_rdma_wr	s_rdma_wr;
-		struct ib_fast_reg_wr	s_fast_reg_wr;
+		struct ib_reg_wr	s_reg_wr;
 	};
 	struct ib_sge		s_sge[RDS_IW_MAX_SGE];
 	unsigned long		s_queued;
@@ -199,7 +198,7 @@
 
 /* Magic WR_ID for ACKs */
 #define RDS_IW_ACK_WR_ID	((u64)0xffffffffffffffffULL)
-#define RDS_IW_FAST_REG_WR_ID	((u64)0xefefefefefefefefULL)
+#define RDS_IW_REG_WR_ID	((u64)0xefefefefefefefefULL)
 #define RDS_IW_LOCAL_INV_WR_ID	((u64)0xdfdfdfdfdfdfdfdfULL)
 
 struct rds_iw_statistics {