IB/rdmavt: Clean up distinction between port number and index

IB core uses 1 relative indexing for ports. All of our data structures
use 0 based indexing. Add an inline function that we can use whenever we
need to validate a legal value and try to convert a port number to a
port index at the entrance into rdmavt.

Try to follow the policy that when we are talking about a port from IB
core point of view we refer to it as a port number. When port is an
index into our arrays refer to it as a port index.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/include/rdma/rdma_vt.h b/include/rdma/rdma_vt.h
index 52dfa9c..5d1c694 100644
--- a/include/rdma/rdma_vt.h
+++ b/include/rdma/rdma_vt.h
@@ -256,7 +256,7 @@
 	void (*notify_new_ah)(struct ib_device *, struct ib_ah_attr *,
 			      struct rvt_ah *);
 	int (*alloc_qpn)(struct rvt_dev_info *rdi, struct rvt_qpn_table *qpt,
-			 enum ib_qp_type type, u8 port, gfp_t gfp);
+			 enum ib_qp_type type, u8 port_num, gfp_t gfp);
 	/**
 	 * Return 0 if modification is valid, -errno otherwise
 	 */
@@ -408,7 +408,7 @@
 void rvt_unregister_device(struct rvt_dev_info *rvd);
 int rvt_check_ah(struct ib_device *ibdev, struct ib_ah_attr *ah_attr);
 int rvt_init_port(struct rvt_dev_info *rdi, struct rvt_ibport *port,
-		  int portnum, u16 *pkey_table);
+		  int port_index, u16 *pkey_table);
 int rvt_rkey_ok(struct rvt_qp *qp, struct rvt_sge *sge,
 		u32 len, u64 vaddr, u32 rkey, int acc);
 int rvt_lkey_ok(struct rvt_lkey_table *rkt, struct rvt_pd *pd,