From: Mike Marciniszyn <mike.marciniszyn@intel.com>
Date: Thu, 1 Feb 2018 10:52:35 -0800
Subject: IB/hfi1: Remove blind constants from 16B update
Patch-mainline: v4.16-rc1
Git-commit: 78d3633ba9c2351fc869271ee00284f46e6b15b2
References: bsc#1060463 FATE#323043

These values were introduced as part of the 16B code to
account for the varying size of the LRH between the differing
packet formats.

Replace the blind constants with defines based on FIELD_SIZEOF()
calls.

Fixes: 5b6cabb0db77 ("IB/hfi1: Add 16B RC/UC support")
Reviewed-by: Don Hiatt <don.hiatt@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/hfi1/driver.c |    6 ++++--
 drivers/infiniband/hw/hfi1/ruc.c    |   13 ++++++-------
 drivers/infiniband/hw/hfi1/ud.c     |   15 ++++++++++-----
 drivers/infiniband/hw/hfi1/verbs.h  |    5 +++++
 4 files changed, 25 insertions(+), 14 deletions(-)

--- a/drivers/infiniband/hw/hfi1/driver.c
+++ b/drivers/infiniband/hw/hfi1/driver.c
@@ -1504,8 +1504,10 @@ static int hfi1_setup_bypass_packet(stru
 
 	/* Query commonly used fields from packet header */
 	packet->opcode = ib_bth_get_opcode(packet->ohdr);
-	packet->hlen = hdr_len_by_opcode[packet->opcode] + 8 + grh_len;
-	packet->payload = packet->ebuf + packet->hlen - (4 * sizeof(u32));
+	/* hdr_len_by_opcode already has an IB LRH factored in */
+	packet->hlen = hdr_len_by_opcode[packet->opcode] +
+		(LRH_16B_BYTES - LRH_9B_BYTES) + grh_len;
+	packet->payload = packet->ebuf + packet->hlen - LRH_16B_BYTES;
 	packet->slid = hfi1_16B_get_slid(packet->hdr);
 	packet->dlid = hfi1_16B_get_dlid(packet->hdr);
 	if (unlikely(hfi1_is_16B_mcast(packet->dlid)))
--- a/drivers/infiniband/hw/hfi1/ruc.c
+++ b/drivers/infiniband/hw/hfi1/ruc.c
@@ -769,8 +769,6 @@ static inline void hfi1_make_ruc_header_
 		struct ib_grh *grh;
 		struct ib_global_route *grd =
 			rdma_ah_retrieve_grh(&qp->remote_ah_attr);
-		int hdrwords;
-
 		/*
 		 * Ensure OPA GIDs are transformed to IB gids
 		 * before creating the GRH.
@@ -779,9 +777,10 @@ static inline void hfi1_make_ruc_header_
 			grd->sgid_index = 0;
 		grh = &ps->s_txreq->phdr.hdr.opah.u.l.grh;
 		l4 = OPA_16B_L4_IB_GLOBAL;
-		hdrwords = ps->s_txreq->hdr_dwords - 4;
-		ps->s_txreq->hdr_dwords += hfi1_make_grh(ibp, grh, grd,
-							 hdrwords, nwords);
+		ps->s_txreq->hdr_dwords +=
+			hfi1_make_grh(ibp, grh, grd,
+				      ps->s_txreq->hdr_dwords - LRH_16B_DWORDS,
+				      nwords);
 		middle = 0;
 	}
 
@@ -837,13 +836,13 @@ static inline void hfi1_make_ruc_header_
 
 	if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
 		struct ib_grh *grh = &ps->s_txreq->phdr.hdr.ibh.u.l.grh;
-		int hdrwords = ps->s_txreq->hdr_dwords - 2;
 
 		lrh0 = HFI1_LRH_GRH;
 		ps->s_txreq->hdr_dwords +=
 			hfi1_make_grh(ibp, grh,
 				      rdma_ah_read_grh(&qp->remote_ah_attr),
-				      hdrwords, nwords);
+				      ps->s_txreq->hdr_dwords - LRH_9B_DWORDS,
+				      nwords);
 		middle = 0;
 	}
 	lrh0 |= (priv->s_sc & 0xf) << 12 |
--- a/drivers/infiniband/hw/hfi1/ud.c
+++ b/drivers/infiniband/hw/hfi1/ud.c
@@ -348,7 +348,8 @@ void hfi1_make_ud_req_9B(struct rvt_qp *
 		grh = &ps->s_txreq->phdr.hdr.ibh.u.l.grh;
 		ps->s_txreq->hdr_dwords +=
 			hfi1_make_grh(ibp, grh, rdma_ah_read_grh(ah_attr),
-				      ps->s_txreq->hdr_dwords - 2, nwords);
+				      ps->s_txreq->hdr_dwords - LRH_9B_DWORDS,
+				      nwords);
 		lrh0 = HFI1_LRH_GRH;
 		ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
 	} else {
@@ -428,8 +429,10 @@ void hfi1_make_ud_req_16B(struct rvt_qp
 			grd->sgid_index = 0;
 		}
 		grh = &ps->s_txreq->phdr.hdr.opah.u.l.grh;
-		ps->s_txreq->hdr_dwords += hfi1_make_grh(ibp, grh, grd,
-					ps->s_txreq->hdr_dwords - 4, nwords);
+		ps->s_txreq->hdr_dwords += hfi1_make_grh(
+			ibp, grh, grd,
+			ps->s_txreq->hdr_dwords - LRH_16B_DWORDS,
+			nwords);
 		ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
 		l4 = OPA_16B_L4_IB_GLOBAL;
 	} else {
@@ -648,7 +651,8 @@ void return_cnp_16B(struct hfi1_ibport *
 		struct ib_grh *grh = &hdr.u.l.grh;
 
 		grh->version_tclass_flow = old_grh->version_tclass_flow;
-		grh->paylen = cpu_to_be16((hwords - 4 + nwords) << 2);
+		grh->paylen = cpu_to_be16(
+			(hwords - LRH_16B_DWORDS + nwords) << 2);
 		grh->hop_limit = 0xff;
 		grh->sgid = old_grh->dgid;
 		grh->dgid = old_grh->sgid;
@@ -702,7 +706,8 @@ void return_cnp(struct hfi1_ibport *ibp,
 		struct ib_grh *grh = &hdr.u.l.grh;
 
 		grh->version_tclass_flow = old_grh->version_tclass_flow;
-		grh->paylen = cpu_to_be16((hwords - 2 + SIZE_OF_CRC) << 2);
+		grh->paylen = cpu_to_be16(
+			(hwords - LRH_9B_DWORDS + SIZE_OF_CRC) << 2);
 		grh->hop_limit = 0xff;
 		grh->sgid = old_grh->dgid;
 		grh->dgid = old_grh->sgid;
--- a/drivers/infiniband/hw/hfi1/verbs.h
+++ b/drivers/infiniband/hw/hfi1/verbs.h
@@ -105,6 +105,11 @@ enum {
 	HFI1_HAS_GRH = (1 << 0),
 };
 
+#define LRH_16B_BYTES (FIELD_SIZEOF(struct hfi1_16b_header, lrh))
+#define LRH_16B_DWORDS (LRH_16B_BYTES / sizeof(u32))
+#define LRH_9B_BYTES (FIELD_SIZEOF(struct ib_header, lrh))
+#define LRH_9B_DWORDS (LRH_9B_BYTES / sizeof(u32))
+
 struct hfi1_16b_header {
 	u32 lrh[4];
 	union {