[dpdk-dev] [PATCH] net/bnxt: fix memory allocation for command response

[Kalesh A P]

From: Kalesh AP <kalesh-anakkur.purayil at broadcom.com>

Driver re-allocates memory for the command response buffer
when the installed firmware version is newer (and has a larger
max response length) than the version of HWRM that was used to
build the PMD.

This change helps to avoid the re-allocation by allocating the
memory for the command response buffer with PAGE_SIZE.

Coverity issue: 366256, 366204, 366180
Fixes: b7778e8a1c00 ("net/bnxt: refactor to properly allocate resources for PF/VF")
Cc: stable at dpdk.org

Signed-off-by: Kalesh AP <kalesh-anakkur.purayil at broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur at broadcom.com>
Reviewed-by: Ajit Kumar Khaparde <ajit.khaparde at broadcom.com>
Reviewed-by: Lance Richardson <lance.richardson at broadcom.com>
---
 drivers/net/bnxt/bnxt_ethdev.c |  2 +-
 drivers/net/bnxt/bnxt_hwrm.c   | 27 ++++-----------------------
 2 files changed, 5 insertions(+), 24 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_ethdev.c b/drivers/net/bnxt/bnxt_ethdev.c
index 3724752..ed2ae45 100644
--- a/drivers/net/bnxt/bnxt_ethdev.c
+++ b/drivers/net/bnxt/bnxt_ethdev.c
@@ -5608,7 +5608,7 @@ static int bnxt_drv_init(struct rte_eth_dev *eth_dev)
 	rc = bnxt_alloc_hwrm_resources(bp);
 	if (rc) {
 		PMD_DRV_LOG(ERR,
-			    "Failed to allocate hwrm resource rc: %x\n", rc);
+			    "Failed to allocate response buffer rc: %x\n", rc);
 		return rc;
 	}
 	rc = bnxt_alloc_leds_info(bp);
diff --git a/drivers/net/bnxt/bnxt_hwrm.c b/drivers/net/bnxt/bnxt_hwrm.c
index e3a0731..6a70b6e 100644
--- a/drivers/net/bnxt/bnxt_hwrm.c
+++ b/drivers/net/bnxt/bnxt_hwrm.c
@@ -1284,28 +1284,8 @@ int bnxt_hwrm_ver_get(struct bnxt *bp, uint32_t timeout)
 	max_resp_len = rte_le_to_cpu_16(resp->max_resp_len);
 	dev_caps_cfg = rte_le_to_cpu_32(resp->dev_caps_cfg);
 
-	if (bp->max_resp_len != max_resp_len) {
-		sprintf(type, "bnxt_hwrm_" PCI_PRI_FMT,
-			bp->pdev->addr.domain, bp->pdev->addr.bus,
-			bp->pdev->addr.devid, bp->pdev->addr.function);
-
-		rte_free(bp->hwrm_cmd_resp_addr);
-
-		bp->hwrm_cmd_resp_addr = rte_malloc(type, max_resp_len, 0);
-		if (bp->hwrm_cmd_resp_addr == NULL) {
-			rc = -ENOMEM;
-			goto error;
-		}
-		bp->hwrm_cmd_resp_dma_addr =
-			rte_malloc_virt2iova(bp->hwrm_cmd_resp_addr);
-		if (bp->hwrm_cmd_resp_dma_addr == RTE_BAD_IOVA) {
-			PMD_DRV_LOG(ERR,
-			"Unable to map response buffer to physical memory.\n");
-			rc = -ENOMEM;
-			goto error;
-		}
-		bp->max_resp_len = max_resp_len;
-	}
+	RTE_VERIFY(max_resp_len <= bp->max_resp_len);
+	bp->max_resp_len = max_resp_len;
 
 	if ((dev_caps_cfg &
 		HWRM_VER_GET_OUTPUT_DEV_CAPS_CFG_SHORT_CMD_SUPPORTED) &&
@@ -2804,7 +2784,7 @@ int bnxt_alloc_hwrm_resources(struct bnxt *bp)
 
 	sprintf(type, "bnxt_hwrm_" PCI_PRI_FMT, pdev->addr.domain,
 		pdev->addr.bus, pdev->addr.devid, pdev->addr.function);
-	bp->max_resp_len = HWRM_MAX_RESP_LEN;
+	bp->max_resp_len = BNXT_PAGE_SIZE;
 	bp->hwrm_cmd_resp_addr = rte_malloc(type, bp->max_resp_len, 0);
 	if (bp->hwrm_cmd_resp_addr == NULL)
 		return -ENOMEM;
@@ -6057,6 +6037,7 @@ int bnxt_hwrm_poll_ver_get(struct bnxt *bp)
 	int rc = 0;
 
 	bp->max_req_len = HWRM_MAX_REQ_LEN;
+	bp->max_resp_len = BNXT_PAGE_SIZE;
 	bp->hwrm_cmd_timeout = SHORT_HWRM_CMD_TIMEOUT;
 
 	HWRM_PREP(&req, HWRM_VER_GET, BNXT_USE_CHIMP_MB);
-- 
2.10.1