RDMA/bnxt_re: Fix the sideband buffer size handling for FW commands

bnxt_qplib_rcfw_alloc_sbuf allocates 24 bytes and it is better to fit
on stack variables. This way we can avoid unwanted kmalloc call.
Call dma_alloc_coherent directly instead of wrapper
bnxt_qplib_rcfw_alloc_sbuf.

Also, FW expects the side buffer  needs to be aligned to
BNXT_QPLIB_CMDQE_UNITS(16B). So align the size to have the
extra padding bytes.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Hongguang Gao <hongguang.gao@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1691052326-32143-4-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

1 files changed, 22 insertions, 16 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_fp.c b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
index f9dee0d2da9c..282e34e8739e 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_fp.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_fp.c
@@ -709,7 +709,7 @@ int bnxt_qplib_query_srq(struct bnxt_qplib_res *res,
 	struct bnxt_qplib_rcfw *rcfw = res->rcfw;
 	struct creq_query_srq_resp resp = {};
 	struct bnxt_qplib_cmdqmsg msg = {};
-	struct bnxt_qplib_rcfw_sbuf *sbuf;
+	struct bnxt_qplib_rcfw_sbuf sbuf;
 	struct creq_query_srq_resp_sb *sb;
 	struct cmdq_query_srq req = {};
 	int rc = 0;
@@ -719,17 +719,20 @@ int bnxt_qplib_query_srq(struct bnxt_qplib_res *res,
 				 sizeof(req));
 
 	/* Configure the request */
-	sbuf = bnxt_qplib_rcfw_alloc_sbuf(rcfw, sizeof(*sb));
-	if (!sbuf)
+	sbuf.size = ALIGN(sizeof(*sb), BNXT_QPLIB_CMDQE_UNITS);
+	sbuf.sb = dma_alloc_coherent(&rcfw->pdev->dev, sbuf.size,
+				     &sbuf.dma_addr, GFP_KERNEL);
+	if (!sbuf.sb)
 		return -ENOMEM;
-	req.resp_size = sizeof(*sb) / BNXT_QPLIB_CMDQE_UNITS;
+	req.resp_size = sbuf.size / BNXT_QPLIB_CMDQE_UNITS;
 	req.srq_cid = cpu_to_le32(srq->id);
-	sb = sbuf->sb;
-	bnxt_qplib_fill_cmdqmsg(&msg, &req, &resp, sbuf, sizeof(req),
+	sb = sbuf.sb;
+	bnxt_qplib_fill_cmdqmsg(&msg, &req, &resp, &sbuf, sizeof(req),
 				sizeof(resp), 0);
 	rc = bnxt_qplib_rcfw_send_message(rcfw, &msg);
 	srq->threshold = le16_to_cpu(sb->srq_limit);
-	bnxt_qplib_rcfw_free_sbuf(rcfw, sbuf);
+	dma_free_coherent(&rcfw->pdev->dev, sbuf.size,
+			  sbuf.sb, sbuf.dma_addr);
 
 	return rc;
 }
@@ -1347,24 +1350,26 @@ int bnxt_qplib_query_qp(struct bnxt_qplib_res *res, struct bnxt_qplib_qp *qp)
 	struct bnxt_qplib_rcfw *rcfw = res->rcfw;
 	struct creq_query_qp_resp resp = {};
 	struct bnxt_qplib_cmdqmsg msg = {};
-	struct bnxt_qplib_rcfw_sbuf *sbuf;
+	struct bnxt_qplib_rcfw_sbuf sbuf;
 	struct creq_query_qp_resp_sb *sb;
 	struct cmdq_query_qp req = {};
 	u32 temp32[4];
 	int i, rc = 0;
 
+	sbuf.size = ALIGN(sizeof(*sb), BNXT_QPLIB_CMDQE_UNITS);
+	sbuf.sb = dma_alloc_coherent(&rcfw->pdev->dev, sbuf.size,
+				     &sbuf.dma_addr, GFP_KERNEL);
+	if (!sbuf.sb)
+		return -ENOMEM;
+	sb = sbuf.sb;
+
 	bnxt_qplib_rcfw_cmd_prep((struct cmdq_base *)&req,
 				 CMDQ_BASE_OPCODE_QUERY_QP,
 				 sizeof(req));
 
-	sbuf = bnxt_qplib_rcfw_alloc_sbuf(rcfw, sizeof(*sb));
-	if (!sbuf)
-		return -ENOMEM;
-	sb = sbuf->sb;
-
 	req.qp_cid = cpu_to_le32(qp->id);
-	req.resp_size = sizeof(*sb) / BNXT_QPLIB_CMDQE_UNITS;
-	bnxt_qplib_fill_cmdqmsg(&msg, &req, &resp, sbuf, sizeof(req),
+	req.resp_size = sbuf.size / BNXT_QPLIB_CMDQE_UNITS;
+	bnxt_qplib_fill_cmdqmsg(&msg, &req, &resp, &sbuf, sizeof(req),
 				sizeof(resp), 0);
 	rc = bnxt_qplib_rcfw_send_message(rcfw, &msg);
 	if (rc)
@@ -1423,7 +1428,8 @@ int bnxt_qplib_query_qp(struct bnxt_qplib_res *res, struct bnxt_qplib_qp *qp)
 	memcpy(qp->smac, sb->src_mac, 6);
 	qp->vlan_id = le16_to_cpu(sb->vlan_pcp_vlan_dei_vlan_id);
 bail:
-	bnxt_qplib_rcfw_free_sbuf(rcfw, sbuf);
+	dma_free_coherent(&rcfw->pdev->dev, sbuf.size,
+			  sbuf.sb, sbuf.dma_addr);
 	return rc;
 }