[dpdk-dev] [PATCH 39/80] net/sfc/base: use MAC stats DMA buffer size from caps

[Andrew Rybchenko <arybchenko@solarflare.com>]

From: Andy Moreton <amoreton@solarflare.com>

For Medford2 the DMA buffer used for one-shot or periodic MAC stats
has been extended. Ensure the MAC stats DMA buffer size is large
enough to hold the number of stats counters supported by firmware.

Signed-off-by: Andy Moreton <amoreton@solarflare.com>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
---
 drivers/net/sfc/base/efx_mcdi.c | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/drivers/net/sfc/base/efx_mcdi.c b/drivers/net/sfc/base/efx_mcdi.c
index a593b3f..a78a226 100644
--- a/drivers/net/sfc/base/efx_mcdi.c
+++ b/drivers/net/sfc/base/efx_mcdi.c
@@ -1791,7 +1791,7 @@ efx_mcdi_mac_stats(
 {
 	efx_mcdi_req_t req;
 	uint8_t payload[MAX(MC_CMD_MAC_STATS_IN_LEN,
-			    MC_CMD_MAC_STATS_OUT_DMA_LEN)];
+			    MC_CMD_MAC_STATS_V2_OUT_DMA_LEN)];
 	int clear = (action == EFX_STATS_CLEAR);
 	int upload = (action == EFX_STATS_UPLOAD);
 	int enable = (action == EFX_STATS_ENABLE_NOEVENTS);
@@ -1804,7 +1804,7 @@ efx_mcdi_mac_stats(
 	req.emr_in_buf = payload;
 	req.emr_in_length = MC_CMD_MAC_STATS_IN_LEN;
 	req.emr_out_buf = payload;
-	req.emr_out_length = MC_CMD_MAC_STATS_OUT_DMA_LEN;
+	req.emr_out_length = MC_CMD_MAC_STATS_V2_OUT_DMA_LEN;
 
 	MCDI_IN_POPULATE_DWORD_6(req, MAC_STATS_IN_CMD,
 	    MAC_STATS_IN_DMA, upload,
@@ -1815,7 +1815,8 @@ efx_mcdi_mac_stats(
 	    MAC_STATS_IN_PERIOD_MS, (enable | events) ? period_ms : 0);
 
 	if (enable || events || upload) {
-		uint32_t bytes = MC_CMD_MAC_NSTATS * sizeof (uint64_t);
+		const efx_nic_cfg_t *encp = &enp->en_nic_cfg;
+		uint32_t bytes;
 
 		/* Periodic stats or stats upload require a DMA buffer */
 		if (esmp == NULL) {
@@ -1823,10 +1824,19 @@ efx_mcdi_mac_stats(
 			goto fail1;
 		}
 
-		EFX_STATIC_ASSERT(MC_CMD_MAC_NSTATS * sizeof (uint64_t) <=
-		    EFX_MAC_STATS_SIZE);
+		if (encp->enc_mac_stats_nstats < MC_CMD_MAC_NSTATS) {
+			/* MAC stats count too small for legacy MAC stats */
+			rc = ENOSPC;
+			goto fail2;
+		}
+
+		bytes = encp->enc_mac_stats_nstats * sizeof (efx_qword_t);
 
-		EFSYS_ASSERT3U(bytes, <=, (uint32_t)EFSYS_MEM_SIZE(esmp));
+		if (EFSYS_MEM_SIZE(esmp) < bytes) {
+			/* DMA buffer too small */
+			rc = ENOSPC;
+			goto fail3;
+		}
 
 		MCDI_IN_SET_DWORD(req, MAC_STATS_IN_DMA_ADDR_LO,
 			    EFSYS_MEM_ADDR(esmp) & 0xffffffff);
@@ -1850,12 +1860,16 @@ efx_mcdi_mac_stats(
 		if ((req.emr_rc != ENOENT) ||
 		    (enp->en_rx_qcount + enp->en_tx_qcount != 0)) {
 			rc = req.emr_rc;
-			goto fail2;
+			goto fail4;
 		}
 	}
 
 	return (0);
 
+fail4:
+	EFSYS_PROBE(fail4);
+fail3:
+	EFSYS_PROBE(fail3);
 fail2:
 	EFSYS_PROBE(fail2);
 fail1:
-- 
2.7.4