[PATCH v2 2/5] scsi: elx: efct: free the HIO when the WQE cannot be built

[Ali Ahmet Memis <ali@iusegentoo.com>]

efct_els_hw_srrs_send() and efct_hw_bls_send() allocate an HIO, ask sli4
to build a WQE into it, and give up when that fails without putting the
HIO back:

	if (sli_els_request64_wqe(&hw->sli, hio->wqe.wqebuf, hio->sgl,
				  &els_params)) {
		efc_log_err(hw->os, "REQ WQE error\n");
		rc = -EIO;
	}

Nothing has been submitted at that point, so no completion will arrive to
release it, and the entry sits on hw->io_inuse until the adapter is torn
down. Each failure costs the pool one entry, and once it is empty
efct_hw_io_alloc() fails and no further ELS, CT or BLS frame can be sent.

Release the HIO on those paths. The efct_hw_wq_write() failure below is
deliberately left alone: it can return an error while this request is
still queued on wq->pending_list, so the HIO cannot be handed back there
without more care.

Fixes: dd53d333aadb ("scsi: elx: efct: Hardware I/O submission routines")
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
---
 drivers/scsi/elx/efct/efct_hw.c | 38 ++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 17 deletions(-)

diff --git a/drivers/scsi/elx/efct/efct_hw.c b/drivers/scsi/elx/efct/efct_hw.c
index 15c37ff1d52e..6cc48fa3e656 100644
--- a/drivers/scsi/elx/efct/efct_hw.c
+++ b/drivers/scsi/elx/efct/efct_hw.c
@@ -2609,6 +2609,7 @@ efct_hw_bls_send(struct efct *efct, u32 type, struct sli_bls_params *bls_params,
 	if (sli_xmit_bls_rsp64_wqe(&hw->sli, hio->wqe.wqebuf,
 				   &bls, bls_params)) {
 		efc_log_err(hw->os, "XMIT_BLS_RSP64 WQE error\n");
+		efct_hw_io_free(hw, hio);
 		return -EIO;
 	}
 
@@ -2820,24 +2821,27 @@ efct_els_hw_srrs_send(struct efc *efc, struct efc_disc_io *io)
 		rc = -EIO;
 	}
 
-	if (rc == 0) {
-		hio->xbusy = true;
+	if (rc) {
+		efct_hw_io_free(hw, hio);
+		return rc;
+	}
 
-		/*
-		 * Add IO to active io wqe list before submitting, in case the
-		 * wcqe processing preempts this thread.
-		 */
-		hio->wq->use_count++;
-		rc = efct_hw_wq_write(hio->wq, &hio->wqe);
-		if (rc >= 0) {
-			/* non-negative return is success */
-			rc = 0;
-		} else {
-			/* failed to write wqe, remove from active wqe list */
-			efc_log_err(hw->os,
-				    "sli_queue_write failed: %d\n", rc);
-			hio->xbusy = false;
-		}
+	hio->xbusy = true;
+
+	/*
+	 * Add IO to active io wqe list before submitting, in case the
+	 * wcqe processing preempts this thread.
+	 */
+	hio->wq->use_count++;
+	rc = efct_hw_wq_write(hio->wq, &hio->wqe);
+	if (rc >= 0) {
+		/* non-negative return is success */
+		rc = 0;
+	} else {
+		/* failed to write wqe, remove from active wqe list */
+		efc_log_err(hw->os,
+			    "sli_queue_write failed: %d\n", rc);
+		hio->xbusy = false;
 	}
 
 	return rc;
-- 
2.55.0