From: James Smart <jsmart2021@gmail.com>
Date: Thu, 7 Sep 2017 13:20:24 -0700
Subject: nvme-fc: use transport-specific sgl format
Patch-mainline: v4.14-rc3
Git-commit: d9d34c0b2327e85da0ad1476575264fe957fc6ef
References: FATE#323952, FATE#322506

Sync with NVM Express spec change and FC-NVME 1.18.

FC transport sets SGL type to Transport SGL Data Block Descriptor and
subtype to transport-specific value 0x0A.

Removed the warn-on's on the PRP fields. They are unneeded. They were
to check for values from the upper layer that weren't set right, and
for the most part were fine. But, with Async events, which reuse the
same structure and 2nd time issued the SGL overlay converted them to
the Transport SGL values - the warn-on's were errantly firing.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/nvme/host/fc.c |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -1989,16 +1989,17 @@ nvme_fc_start_fcp_op(struct nvme_fc_ctrl
 	 * as well as those by FC-NVME spec.
 	 */
 	WARN_ON_ONCE(sqe->common.metadata);
-	WARN_ON_ONCE(sqe->common.dptr.prp1);
-	WARN_ON_ONCE(sqe->common.dptr.prp2);
 	sqe->common.flags |= NVME_CMD_SGL_METABUF;
 
 	/*
-	 * format SQE DPTR field per FC-NVME rules
-	 *    type=data block descr; subtype=offset;
-	 *    offset is currently 0.
+	 * format SQE DPTR field per FC-NVME rules:
+	 *    type=0x5     Transport SGL Data Block Descriptor
+	 *    subtype=0xA  Transport-specific value
+	 *    address=0
+	 *    length=length of the data series
 	 */
-	sqe->rw.dptr.sgl.type = NVME_SGL_FMT_OFFSET;
+	sqe->rw.dptr.sgl.type = (NVME_TRANSPORT_SGL_DATA_DESC << 4) |
+					NVME_SGL_FMT_TRANSPORT_A;
 	sqe->rw.dptr.sgl.length = cpu_to_le32(data_len);
 	sqe->rw.dptr.sgl.addr = 0;