RDMA/bnxt_re: Fixing the Control path command and response handling

Fixing a concurrency issue with creq handling. Each caller
was given a globally managed crsq element, which was
accessed outside a lock. This could result in corruption,
if lot of applications are simultaneously issuing Control Path
commands. Now, each caller will provide its own response buffer
and the responses will be copied under a lock.
Also, Fixing the queue full condition check for the CMDQ.

As a part of these changes, the control path code is refactored
to remove the code replication in the response status checking.

Signed-off-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 164 insertions, 150 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
index 23fb7260662b..16e42754dbec 100644
--- a/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
+++ b/drivers/infiniband/hw/bnxt_re/qplib_rcfw.c
@@ -39,72 +39,55 @@
 #include <linux/spinlock.h>
 #include <linux/pci.h>
 #include <linux/prefetch.h>
+#include <linux/delay.h>
+
 #include "roce_hsi.h"
 #include "qplib_res.h"
 #include "qplib_rcfw.h"
 static void bnxt_qplib_service_creq(unsigned long data);
 
 /* Hardware communication channel */
-int bnxt_qplib_rcfw_wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
+static int __wait_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
 {
 	u16 cbit;
 	int rc;
 
-	cookie &= RCFW_MAX_COOKIE_VALUE;
 	cbit = cookie % RCFW_MAX_OUTSTANDING_CMD;
-	if (!test_bit(cbit, rcfw->cmdq_bitmap))
-		dev_warn(&rcfw->pdev->dev,
-			 "QPLIB: CMD bit %d for cookie 0x%x is not set?",
-			 cbit, cookie);
-
 	rc = wait_event_timeout(rcfw->waitq,
 				!test_bit(cbit, rcfw->cmdq_bitmap),
 				msecs_to_jiffies(RCFW_CMD_WAIT_TIME_MS));
-	if (!rc) {
-		dev_warn(&rcfw->pdev->dev,
-			 "QPLIB: Bono Error: timeout %d msec, msg {0x%x}\n",
-			 RCFW_CMD_WAIT_TIME_MS, cookie);
-	}
-
-	return rc;
+	return rc ? 0 : -ETIMEDOUT;
 };
 
-int bnxt_qplib_rcfw_block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
+static int __block_for_resp(struct bnxt_qplib_rcfw *rcfw, u16 cookie)
 {
-	u32 count = -1;
+	u32 count = RCFW_BLOCKED_CMD_WAIT_COUNT;
 	u16 cbit;
 
-	cookie &= RCFW_MAX_COOKIE_VALUE;
 	cbit = cookie % RCFW_MAX_OUTSTANDING_CMD;
 	if (!test_bit(cbit, rcfw->cmdq_bitmap))
 		goto done;
 	do {
+		mdelay(1); /* 1m sec */
 		bnxt_qplib_service_creq((unsigned long)rcfw);
 	} while (test_bit(cbit, rcfw->cmdq_bitmap) && --count);
 done:
-	return count;
+	return count ? 0 : -ETIMEDOUT;
 };
 
-void *bnxt_qplib_rcfw_send_message(struct bnxt_qplib_rcfw *rcfw,
-				   struct cmdq_base *req, void **crsbe,
-				   u8 is_block)
+static int __send_message(struct bnxt_qplib_rcfw *rcfw, struct cmdq_base *req,
+			  struct creq_base *resp, void *sb, u8 is_block)
 {
-	struct bnxt_qplib_crsq *crsq = &rcfw->crsq;
 	struct bnxt_qplib_cmdqe *cmdqe, **cmdq_ptr;
 	struct bnxt_qplib_hwq *cmdq = &rcfw->cmdq;
-	struct bnxt_qplib_hwq *crsb = &rcfw->crsb;
-	struct bnxt_qplib_crsqe *crsqe = NULL;
-	struct bnxt_qplib_crsbe **crsb_ptr;
+	struct bnxt_qplib_crsq *crsqe;
 	u32 sw_prod, cmdq_prod;
-	u8 retry_cnt = 0xFF;
-	dma_addr_t dma_addr;
 	unsigned long flags;
 	u32 size, opcode;
 	u16 cookie, cbit;
 	int pg, idx;
 	u8 *preq;
 
-retry:
 	opcode = req->opcode;
 	if (!test_bit(FIRMWARE_INITIALIZED_FLAG, &rcfw->flags) &&
 	    (opcode != CMDQ_BASE_OPCODE_QUERY_FUNC &&
@@ -112,63 +95,50 @@ retry:
 		dev_err(&rcfw->pdev->dev,
 			"QPLIB: RCFW not initialized, reject opcode 0x%x",
 			opcode);
-		return NULL;
+		return -EINVAL;
 	}
 
 	if (test_bit(FIRMWARE_INITIALIZED_FLAG, &rcfw->flags) &&
 	    opcode == CMDQ_BASE_OPCODE_INITIALIZE_FW) {
 		dev_err(&rcfw->pdev->dev, "QPLIB: RCFW already initialized!");
-		return NULL;
+		return -EINVAL;
 	}
 
 	/* Cmdq are in 16-byte units, each request can consume 1 or more
 	 * cmdqe
 	 */
 	spin_lock_irqsave(&cmdq->lock, flags);
-	if (req->cmd_size > cmdq->max_elements -
-	    ((HWQ_CMP(cmdq->prod, cmdq) - HWQ_CMP(cmdq->cons, cmdq)) &
-	     (cmdq->max_elements - 1))) {
+	if (req->cmd_size >= HWQ_FREE_SLOTS(cmdq)) {
 		dev_err(&rcfw->pdev->dev, "QPLIB: RCFW: CMDQ is full!");
 		spin_unlock_irqrestore(&cmdq->lock, flags);
-
-		if (!retry_cnt--)
-			return NULL;
-		goto retry;
+		return -EAGAIN;
 	}
 
-	retry_cnt = 0xFF;
 
-	cookie = atomic_inc_return(&rcfw->seq_num) & RCFW_MAX_COOKIE_VALUE;
+	cookie = rcfw->seq_num & RCFW_MAX_COOKIE_VALUE;
 	cbit = cookie % RCFW_MAX_OUTSTANDING_CMD;
 	if (is_block)
 		cookie |= RCFW_CMD_IS_BLOCKING;
+
+	set_bit(cbit, rcfw->cmdq_bitmap);
 	req->cookie = cpu_to_le16(cookie);
-	if (test_and_set_bit(cbit, rcfw->cmdq_bitmap)) {
-		dev_err(&rcfw->pdev->dev,
-			"QPLIB: RCFW MAX outstanding cmd reached!");
-		atomic_dec(&rcfw->seq_num);
+	crsqe = &rcfw->crsqe_tbl[cbit];
+	if (crsqe->resp) {
 		spin_unlock_irqrestore(&cmdq->lock, flags);
-
-		if (!retry_cnt--)
-			return NULL;
-		goto retry;
+		return -EBUSY;
 	}
-	/* Reserve a resp buffer slot if requested */
-	if (req->resp_size && crsbe) {
-		spin_lock(&crsb->lock);
-		sw_prod = HWQ_CMP(crsb->prod, crsb);
-		crsb_ptr = (struct bnxt_qplib_crsbe **)crsb->pbl_ptr;
-		*crsbe = (void *)&crsb_ptr[get_crsb_pg(sw_prod)]
-					  [get_crsb_idx(sw_prod)];
-		bnxt_qplib_crsb_dma_next(crsb->pbl_dma_ptr, sw_prod, &dma_addr);
-		req->resp_addr = cpu_to_le64(dma_addr);
-		crsb->prod++;
-		spin_unlock(&crsb->lock);
-
-		req->resp_size = (sizeof(struct bnxt_qplib_crsbe) +
-				  BNXT_QPLIB_CMDQE_UNITS - 1) /
-				 BNXT_QPLIB_CMDQE_UNITS;
+	memset(resp, 0, sizeof(*resp));
+	crsqe->resp = (struct creq_qp_event *)resp;
+	crsqe->resp->cookie = req->cookie;
+	crsqe->req_size = req->cmd_size;
+	if (req->resp_size && sb) {
+		struct bnxt_qplib_rcfw_sbuf *sbuf = sb;
+
+		req->resp_addr = cpu_to_le64(sbuf->dma_addr);
+		req->resp_size = (sbuf->size + BNXT_QPLIB_CMDQE_UNITS - 1) /
+				  BNXT_QPLIB_CMDQE_UNITS;
 	}
+
 	cmdq_ptr = (struct bnxt_qplib_cmdqe **)cmdq->pbl_ptr;
 	preq = (u8 *)req;
 	size = req->cmd_size * BNXT_QPLIB_CMDQE_UNITS;
@@ -190,23 +160,24 @@ retry:
 		preq += min_t(u32, size, sizeof(*cmdqe));
 		size -= min_t(u32, size, sizeof(*cmdqe));
 		cmdq->prod++;
+		rcfw->seq_num++;
 	} while (size > 0);
 
+	rcfw->seq_num++;
+
 	cmdq_prod = cmdq->prod;
 	if (rcfw->flags & FIRMWARE_FIRST_FLAG) {
-		/* The very first doorbell write is required to set this flag
-		 * which prompts the FW to reset its internal pointers
+		/* The very first doorbell write
+		 * is required to set this flag
+		 * which prompts the FW to reset
+		 * its internal pointers
 		 */
 		cmdq_prod |= FIRMWARE_FIRST_FLAG;
 		rcfw->flags &= ~FIRMWARE_FIRST_FLAG;
 	}
-	sw_prod = HWQ_CMP(crsq->prod, crsq);
-	crsqe = &crsq->crsq[sw_prod];
-	memset(crsqe, 0, sizeof(*crsqe));
-	crsq->prod++;
-	crsqe->req_size = req->cmd_size;
 
 	/* ring CMDQ DB */
+	wmb();
 	writel(cmdq_prod, rcfw->cmdq_bar_reg_iomem +
 	       rcfw->cmdq_bar_reg_prod_off);
 	writel(RCFW_CMDQ_TRIG_VAL, rcfw->cmdq_bar_reg_iomem +
@@ -214,9 +185,56 @@ retry:
 done:
 	spin_unlock_irqrestore(&cmdq->lock, flags);
 	/* Return the CREQ response pointer */
-	return crsqe ? &crsqe->qp_event : NULL;
+	return 0;
 }
 
+int bnxt_qplib_rcfw_send_message(struct bnxt_qplib_rcfw *rcfw,
+				 struct cmdq_base *req,
+				 struct creq_base *resp,
+				 void *sb, u8 is_block)
+{
+	struct creq_qp_event *evnt = (struct creq_qp_event *)resp;
+	u16 cookie;
+	u8 opcode, retry_cnt = 0xFF;
+	int rc = 0;
+
+	do {
+		opcode = req->opcode;
+		rc = __send_message(rcfw, req, resp, sb, is_block);
+		cookie = le16_to_cpu(req->cookie) & RCFW_MAX_COOKIE_VALUE;
+		if (!rc)
+			break;
+
+		if (!retry_cnt || (rc != -EAGAIN && rc != -EBUSY)) {
+			/* send failed */
+			dev_err(&rcfw->pdev->dev, "QPLIB: cmdq[%#x]=%#x send failed",
+				cookie, opcode);
+			return rc;
+		}
+		is_block ? mdelay(1) : usleep_range(500, 1000);
+
+	} while (retry_cnt--);
+
+	if (is_block)
+		rc = __block_for_resp(rcfw, cookie);
+	else
+		rc = __wait_for_resp(rcfw, cookie);
+	if (rc) {
+		/* timed out */
+		dev_err(&rcfw->pdev->dev, "QPLIB: cmdq[%#x]=%#x timedout (%d)msec",
+			cookie, opcode, RCFW_CMD_WAIT_TIME_MS);
+		return rc;
+	}
+
+	if (evnt->status) {
+		/* failed with status */
+		dev_err(&rcfw->pdev->dev, "QPLIB: cmdq[%#x]=%#x status %#x",
+			cookie, opcode, evnt->status);
+		rc = -EFAULT;
+	}
+
+	return rc;
+}
 /* Completions */
 static int bnxt_qplib_process_func_event(struct bnxt_qplib_rcfw *rcfw,
 					 struct creq_func_event *func_event)
@@ -260,12 +278,12 @@ static int bnxt_qplib_process_func_event(struct bnxt_qplib_rcfw *rcfw,
 static int bnxt_qplib_process_qp_event(struct bnxt_qplib_rcfw *rcfw,
 				       struct creq_qp_event *qp_event)
 {
-	struct bnxt_qplib_crsq *crsq = &rcfw->crsq;
 	struct bnxt_qplib_hwq *cmdq = &rcfw->cmdq;
-	struct bnxt_qplib_crsqe *crsqe;
-	u16 cbit, cookie, blocked = 0;
+	struct bnxt_qplib_crsq *crsqe;
 	unsigned long flags;
-	u32 sw_cons;
+	u16 cbit, blocked = 0;
+	u16 cookie;
+	__le16  mcookie;
 
 	switch (qp_event->event) {
 	case CREQ_QP_EVENT_EVENT_QP_ERROR_NOTIFICATION:
@@ -275,24 +293,31 @@ static int bnxt_qplib_process_qp_event(struct bnxt_qplib_rcfw *rcfw,
 	default:
 		/* Command Response */
 		spin_lock_irqsave(&cmdq->lock, flags);
-		sw_cons = HWQ_CMP(crsq->cons, crsq);
-		crsqe = &crsq->crsq[sw_cons];
-		crsq->cons++;
-		memcpy(&crsqe->qp_event, qp_event, sizeof(crsqe->qp_event));
-
-		cookie = le16_to_cpu(crsqe->qp_event.cookie);
+		cookie = le16_to_cpu(qp_event->cookie);
+		mcookie = qp_event->cookie;
 		blocked = cookie & RCFW_CMD_IS_BLOCKING;
 		cookie &= RCFW_MAX_COOKIE_VALUE;
 		cbit = cookie % RCFW_MAX_OUTSTANDING_CMD;
+		crsqe = &rcfw->crsqe_tbl[cbit];
+		if (crsqe->resp &&
+		    crsqe->resp->cookie  == mcookie) {
+			memcpy(crsqe->resp, qp_event, sizeof(*qp_event));
+			crsqe->resp = NULL;
+		} else {
+			dev_err(&rcfw->pdev->dev,
+				"QPLIB: CMD %s resp->cookie = %#x, evnt->cookie = %#x",
+				crsqe->resp ? "mismatch" : "collision",
+				crsqe->resp ? crsqe->resp->cookie : 0, mcookie);
+		}
 		if (!test_and_clear_bit(cbit, rcfw->cmdq_bitmap))
 			dev_warn(&rcfw->pdev->dev,
 				 "QPLIB: CMD bit %d was not requested", cbit);
-
 		cmdq->cons += crsqe->req_size;
-		spin_unlock_irqrestore(&cmdq->lock, flags);
+		crsqe->req_size = 0;
+
 		if (!blocked)
 			wake_up(&rcfw->waitq);
-		break;
+		spin_unlock_irqrestore(&cmdq->lock, flags);
 	}
 	return 0;
 }
@@ -305,12 +330,12 @@ static void bnxt_qplib_service_creq(unsigned long data)
 	struct creq_base *creqe, **creq_ptr;
 	u32 sw_cons, raw_cons;
 	unsigned long flags;
-	u32 type;
+	u32 type, budget = CREQ_ENTRY_POLL_BUDGET;
 
-	/* Service the CREQ until empty */
+	/* Service the CREQ until budget is over */
 	spin_lock_irqsave(&creq->lock, flags);
 	raw_cons = creq->cons;
-	while (1) {
+	while (budget > 0) {
 		sw_cons = HWQ_CMP(raw_cons, creq);
 		creq_ptr = (struct creq_base **)creq->pbl_ptr;
 		creqe = &creq_ptr[get_creq_pg(sw_cons)][get_creq_idx(sw_cons)];
@@ -320,15 +345,9 @@ static void bnxt_qplib_service_creq(unsigned long data)
 		type = creqe->type & CREQ_BASE_TYPE_MASK;
 		switch (type) {
 		case CREQ_BASE_TYPE_QP_EVENT:
-			if (!bnxt_qplib_process_qp_event
-			    (rcfw, (struct creq_qp_event *)creqe))
-				rcfw->creq_qp_event_processed++;
-			else {
-				dev_warn(&rcfw->pdev->dev, "QPLIB: crsqe with");
-				dev_warn(&rcfw->pdev->dev,
-					 "QPLIB: type = 0x%x not handled",
-					 type);
-			}
+			bnxt_qplib_process_qp_event
+				(rcfw, (struct creq_qp_event *)creqe);
+			rcfw->creq_qp_event_processed++;
 			break;
 		case CREQ_BASE_TYPE_FUNC_EVENT:
 			if (!bnxt_qplib_process_func_event
@@ -346,7 +365,9 @@ static void bnxt_qplib_service_creq(unsigned long data)
 			break;
 		}
 		raw_cons++;
+		budget--;
 	}
+
 	if (creq->cons != raw_cons) {
 		creq->cons = raw_cons;
 		CREQ_DB_REARM(rcfw->creq_bar_reg_iomem, raw_cons,
@@ -375,23 +396,16 @@ static irqreturn_t bnxt_qplib_creq_irq(int irq, void *dev_instance)
 /* RCFW */
 int bnxt_qplib_deinit_rcfw(struct bnxt_qplib_rcfw *rcfw)
 {
-	struct creq_deinitialize_fw_resp *resp;
 	struct cmdq_deinitialize_fw req;
+	struct creq_deinitialize_fw_resp resp;
 	u16 cmd_flags = 0;
+	int rc;
 
 	RCFW_CMD_PREP(req, DEINITIALIZE_FW, cmd_flags);
-	resp = (struct creq_deinitialize_fw_resp *)
-			bnxt_qplib_rcfw_send_message(rcfw, (void *)&req,
-						     NULL, 0);
-	if (!resp)
-		return -EINVAL;
-
-	if (!bnxt_qplib_rcfw_wait_for_resp(rcfw, le16_to_cpu(req.cookie)))
-		return -ETIMEDOUT;
-
-	if (resp->status ||
-	    le16_to_cpu(resp->cookie) != le16_to_cpu(req.cookie))
-		return -EFAULT;
+	rc = bnxt_qplib_rcfw_send_message(rcfw, (void *)&req, (void *)&resp,
+					  NULL, 0);
+	if (rc)
+		return rc;
 
 	clear_bit(FIRMWARE_INITIALIZED_FLAG, &rcfw->flags);
 	return 0;
@@ -417,9 +431,10 @@ static int __get_pbl_pg_idx(struct bnxt_qplib_pbl *pbl)
 int bnxt_qplib_init_rcfw(struct bnxt_qplib_rcfw *rcfw,
 			 struct bnxt_qplib_ctx *ctx, int is_virtfn)
 {
-	struct creq_initialize_fw_resp *resp;
 	struct cmdq_initialize_fw req;
+	struct creq_initialize_fw_resp resp;
 	u16 cmd_flags = 0, level;
+	int rc;
 
 	RCFW_CMD_PREP(req, INITIALIZE_FW, cmd_flags);
 
@@ -482,37 +497,19 @@ int bnxt_qplib_init_rcfw(struct bnxt_qplib_rcfw *rcfw,
 
 skip_ctx_setup:
 	req.stat_ctx_id = cpu_to_le32(ctx->stats.fw_id);
-	resp = (struct creq_initialize_fw_resp *)
-			bnxt_qplib_rcfw_send_message(rcfw, (void *)&req,
-						     NULL, 0);
-	if (!resp) {
-		dev_err(&rcfw->pdev->dev,
-			"QPLIB: RCFW: INITIALIZE_FW send failed");
-		return -EINVAL;
-	}
-	if (!bnxt_qplib_rcfw_wait_for_resp(rcfw, le16_to_cpu(req.cookie))) {
-		/* Cmd timed out */
-		dev_err(&rcfw->pdev->dev,
-			"QPLIB: RCFW: INITIALIZE_FW timed out");
-		return -ETIMEDOUT;
-	}
-	if (resp->status ||
-	    le16_to_cpu(resp->cookie) != le16_to_cpu(req.cookie)) {
-		dev_err(&rcfw->pdev->dev,
-			"QPLIB: RCFW: INITIALIZE_FW failed");
-		return -EINVAL;
-	}
+	rc = bnxt_qplib_rcfw_send_message(rcfw, (void *)&req, (void *)&resp,
+					  NULL, 0);
+	if (rc)
+		return rc;
 	set_bit(FIRMWARE_INITIALIZED_FLAG, &rcfw->flags);
 	return 0;
 }
 
 void bnxt_qplib_free_rcfw_channel(struct bnxt_qplib_rcfw *rcfw)
 {
-	bnxt_qplib_free_hwq(rcfw->pdev, &rcfw->crsb);
-	kfree(rcfw->crsq.crsq);
+	kfree(rcfw->crsqe_tbl);
 	bnxt_qplib_free_hwq(rcfw->pdev, &rcfw->cmdq);
 	bnxt_qplib_free_hwq(rcfw->pdev, &rcfw->creq);
-
 	rcfw->pdev = NULL;
 }
 
@@ -539,21 +536,11 @@ int bnxt_qplib_alloc_rcfw_channel(struct pci_dev *pdev,
 		goto fail;
 	}
 
-	rcfw->crsq.max_elements = rcfw->cmdq.max_elements;
-	rcfw->crsq.crsq = kcalloc(rcfw->crsq.max_elements,
-				  sizeof(*rcfw->crsq.crsq), GFP_KERNEL);
-	if (!rcfw->crsq.crsq)
+	rcfw->crsqe_tbl = kcalloc(rcfw->cmdq.max_elements,
+				  sizeof(*rcfw->crsqe_tbl), GFP_KERNEL);
+	if (!rcfw->crsqe_tbl)
 		goto fail;
 
-	rcfw->crsb.max_elements = BNXT_QPLIB_CRSBE_MAX_CNT;
-	if (bnxt_qplib_alloc_init_hwq(rcfw->pdev, &rcfw->crsb, NULL, 0,
-				      &rcfw->crsb.max_elements,
-				      BNXT_QPLIB_CRSBE_UNITS, 0, PAGE_SIZE,
-				      HWQ_TYPE_CTX)) {
-		dev_err(&rcfw->pdev->dev,
-			"QPLIB: HW channel CRSB allocation failed");
-		goto fail;
-	}
 	return 0;
 
 fail:
@@ -606,7 +593,7 @@ int bnxt_qplib_enable_rcfw_channel(struct pci_dev *pdev,
 	int rc;
 
 	/* General */
-	atomic_set(&rcfw->seq_num, 0);
+	rcfw->seq_num = 0;
 	rcfw->flags = FIRMWARE_FIRST_FLAG;
 	bmap_size = BITS_TO_LONGS(RCFW_MAX_OUTSTANDING_CMD *
 				  sizeof(unsigned long));
@@ -636,10 +623,6 @@ int bnxt_qplib_enable_rcfw_channel(struct pci_dev *pdev,
 
 	rcfw->cmdq_bar_reg_trig_off = RCFW_COMM_TRIG_OFFSET;
 
-	/* CRSQ */
-	rcfw->crsq.prod = 0;
-	rcfw->crsq.cons = 0;
-
 	/* CREQ */
 	rcfw->creq_bar_reg = RCFW_COMM_CONS_PCI_BAR_REGION;
 	res_base = pci_resource_start(pdev, rcfw->creq_bar_reg);
@@ -692,3 +675,34 @@ int bnxt_qplib_enable_rcfw_channel(struct pci_dev *pdev,
 	__iowrite32_copy(rcfw->cmdq_bar_reg_iomem, &init, sizeof(init) / 4);
 	return 0;
 }
+
+struct bnxt_qplib_rcfw_sbuf *bnxt_qplib_rcfw_alloc_sbuf(
+		struct bnxt_qplib_rcfw *rcfw,
+		u32 size)
+{
+	struct bnxt_qplib_rcfw_sbuf *sbuf;
+
+	sbuf = kzalloc(sizeof(*sbuf), GFP_ATOMIC);
+	if (!sbuf)
+		return NULL;
+
+	sbuf->size = size;
+	sbuf->sb = dma_zalloc_coherent(&rcfw->pdev->dev, sbuf->size,
+				       &sbuf->dma_addr, GFP_ATOMIC);
+	if (!sbuf->sb)
+		goto bail;
+
+	return sbuf;
+bail:
+	kfree(sbuf);
+	return NULL;
+}
+
+void bnxt_qplib_rcfw_free_sbuf(struct bnxt_qplib_rcfw *rcfw,
+			       struct bnxt_qplib_rcfw_sbuf *sbuf)
+{
+	if (sbuf->sb)
+		dma_free_coherent(&rcfw->pdev->dev, sbuf->size,
+				  sbuf->sb, sbuf->dma_addr);
+	kfree(sbuf);
+}