[PATCH v4 4/5] nvme-rdma: avoid IO error for nvme native multipath

[Chao Leng]

Work with nvme native multipath, if a path related error occurs when
queue_rq call HBA drive to send request, queue_rq will return
BLK_STS_IOERR to blk-mq. The request is completed with BLK_STS_IOERR
instead of fail over to retry.
queue_rq need call nvme_complete_rq to complete the request with
NVME_SC_HOST_PATH_ERROR, the request will fail over to retry if needed.

Signed-off-by: Chao Leng <lengchao at huawei.com>
---
 drivers/nvme/host/rdma.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index b7ce4f221d99..7c801132d5ed 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -2037,6 +2037,7 @@ static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
 	bool queue_ready = test_bit(NVME_RDMA_Q_LIVE, &queue->flags);
 	blk_status_t ret;
 	int err;
+	bool driver_error = false;
 
 	WARN_ON_ONCE(rq->tag < 0);
 
@@ -2084,8 +2085,10 @@ static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
 
 	err = nvme_rdma_post_send(queue, sqe, req->sge, req->num_sge,
 			req->mr ? &req->reg_wr.wr : NULL);
-	if (unlikely(err))
+	if (unlikely(err)) {
+		driver_error = true;
 		goto err_unmap;
+	}
 
 	return BLK_STS_OK;
 
@@ -2100,6 +2103,10 @@ static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
 unmap_qe:
 	ib_dma_unmap_single(dev, req->sqe.dma, sizeof(struct nvme_command),
 			    DMA_TO_DEVICE);
+	if (driver_error && ret == BLK_STS_IOERR) {
+		nvme_complete_failed_rq(rq, NVME_SC_HOST_PATH_ERROR);
+		ret = BLK_STS_OK;
+	}
 	return ret;
 }
 
-- 
2.16.4