[dpdk-dev] [PATCH] net/enic: fix segfault due to static max number of queues

[John Daley <johndale@cisco.com>]

From: Hyong Youb Kim <hyonkim@cisco.com>

ENIC_CQ_MAX, ENIC_WQ_MAX and others are arbitrary values that
prevent the app from using more queues when they are available on
hardware. Remove them and dynamically allocate vnic_cq and such
arrays to accommodate all available hardware queues.

As a side effect of removing ENIC_CQ_MAX, this commit fixes a segfault
that would happen when the app requests more than 16 CQs, because
enic_set_vnic_res() does not consider ENIC_CQ_MAX. For example, the
following command causes a crash.

testpmd -- --rxq=16 --txq=16

Fixes: ce93d3c36db0 ("net/enic: fix resource check failures when bonding devices")
Cc: stable@dpdk.org

Signed-off-by: Hyong Youb Kim <hyonkim@cisco.com>
Reviewed-by: John Daley <johndale@cisco.com>
---
 drivers/net/enic/enic.h        | 25 +++++++++---------------
 drivers/net/enic/enic_ethdev.c | 20 ++------------------
 drivers/net/enic/enic_main.c   | 43 ++++++++++++++++++++++++++++++++----------
 3 files changed, 44 insertions(+), 44 deletions(-)

diff --git a/drivers/net/enic/enic.h b/drivers/net/enic/enic.h
index c3ed1fa02..c76a8f0af 100644
--- a/drivers/net/enic/enic.h
+++ b/drivers/net/enic/enic.h
@@ -24,13 +24,6 @@
 #define DRV_DESCRIPTION		"Cisco VIC Ethernet NIC Poll-mode Driver"
 #define DRV_COPYRIGHT		"Copyright 2008-2015 Cisco Systems, Inc"
 
-#define ENIC_WQ_MAX		8
-/* With Rx scatter support, we use two RQs on VIC per RQ used by app. Both
- * RQs use the same CQ.
- */
-#define ENIC_RQ_MAX		16
-#define ENIC_CQ_MAX		(ENIC_WQ_MAX + (ENIC_RQ_MAX / 2))
-#define ENIC_INTR_MAX		(ENIC_CQ_MAX + 2)
 #define ENIC_MAX_MAC_ADDR	64
 
 #define VLAN_ETH_HLEN           18
@@ -121,17 +114,17 @@ struct enic {
 	unsigned int flags;
 	unsigned int priv_flags;
 
-	/* work queue */
-	struct vnic_wq wq[ENIC_WQ_MAX];
-	unsigned int wq_count;
+	/* work queue (len = conf_wq_count) */
+	struct vnic_wq *wq;
+	unsigned int wq_count; /* equals eth_dev nb_tx_queues */
 
-	/* receive queue */
-	struct vnic_rq rq[ENIC_RQ_MAX];
-	unsigned int rq_count;
+	/* receive queue (len = conf_rq_count) */
+	struct vnic_rq *rq;
+	unsigned int rq_count; /* equals eth_dev nb_rx_queues */
 
-	/* completion queue */
-	struct vnic_cq cq[ENIC_CQ_MAX];
-	unsigned int cq_count;
+	/* completion queue (len = conf_cq_count) */
+	struct vnic_cq *cq;
+	unsigned int cq_count; /* equals rq_count + wq_count */
 
 	/* interrupt resource */
 	struct vnic_intr intr;
diff --git a/drivers/net/enic/enic_ethdev.c b/drivers/net/enic/enic_ethdev.c
index e1ff9dcbd..2c356dc27 100644
--- a/drivers/net/enic/enic_ethdev.c
+++ b/drivers/net/enic/enic_ethdev.c
@@ -190,13 +190,7 @@ static int enicpmd_dev_tx_queue_setup(struct rte_eth_dev *eth_dev,
 		return -E_RTE_SECONDARY;
 
 	ENICPMD_FUNC_TRACE();
-	if (queue_idx >= ENIC_WQ_MAX) {
-		dev_err(enic,
-			"Max number of TX queues exceeded.  Max is %d\n",
-			ENIC_WQ_MAX);
-		return -EINVAL;
-	}
-
+	RTE_ASSERT(queue_idx < enic->conf_wq_count);
 	eth_dev->data->tx_queues[queue_idx] = (void *)&enic->wq[queue_idx];
 
 	ret = enic_alloc_wq(enic, queue_idx, socket_id, nb_desc);
@@ -310,17 +304,7 @@ static int enicpmd_dev_rx_queue_setup(struct rte_eth_dev *eth_dev,
 
 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
 		return -E_RTE_SECONDARY;
-
-	/* With Rx scatter support, two RQs are now used on VIC per RQ used
-	 * by the application.
-	 */
-	if (queue_idx * 2 >= ENIC_RQ_MAX) {
-		dev_err(enic,
-			"Max number of RX queues exceeded.  Max is %d. This PMD uses 2 RQs on VIC per RQ used by DPDK.\n",
-			ENIC_RQ_MAX);
-		return -EINVAL;
-	}
-
+	RTE_ASSERT(enic_rte_rq_idx_to_sop_idx(queue_idx) < enic->conf_rq_count);
 	eth_dev->data->rx_queues[queue_idx] =
 		(void *)&enic->rq[enic_rte_rq_idx_to_sop_idx(queue_idx)];
 
diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 9274defd9..ec9d343fd 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -1042,6 +1042,9 @@ static void enic_dev_deinit(struct enic *enic)
 	vnic_dev_notify_unset(enic->vdev);
 
 	rte_free(eth_dev->data->mac_addrs);
+	rte_free(enic->cq);
+	rte_free(enic->rq);
+	rte_free(enic->wq);
 }
 
 
@@ -1049,27 +1052,28 @@ int enic_set_vnic_res(struct enic *enic)
 {
 	struct rte_eth_dev *eth_dev = enic->rte_dev;
 	int rc = 0;
+	unsigned int required_rq, required_wq, required_cq;
 
-	/* With Rx scatter support, two RQs are now used per RQ used by
-	 * the application.
-	 */
-	if (enic->conf_rq_count < eth_dev->data->nb_rx_queues) {
+	/* Always use two vNIC RQs per eth_dev RQ, regardless of Rx scatter. */
+	required_rq = eth_dev->data->nb_rx_queues * 2;
+	required_wq = eth_dev->data->nb_tx_queues;
+	required_cq = eth_dev->data->nb_rx_queues + eth_dev->data->nb_tx_queues;
+
+	if (enic->conf_rq_count < required_rq) {
 		dev_err(dev, "Not enough Receive queues. Requested:%u which uses %d RQs on VIC, Configured:%u\n",
 			eth_dev->data->nb_rx_queues,
-			eth_dev->data->nb_rx_queues * 2, enic->conf_rq_count);
+			required_rq, enic->conf_rq_count);
 		rc = -EINVAL;
 	}
-	if (enic->conf_wq_count < eth_dev->data->nb_tx_queues) {
+	if (enic->conf_wq_count < required_wq) {
 		dev_err(dev, "Not enough Transmit queues. Requested:%u, Configured:%u\n",
 			eth_dev->data->nb_tx_queues, enic->conf_wq_count);
 		rc = -EINVAL;
 	}
 
-	if (enic->conf_cq_count < (eth_dev->data->nb_rx_queues +
-				   eth_dev->data->nb_tx_queues)) {
+	if (enic->conf_cq_count < required_cq) {
 		dev_err(dev, "Not enough Completion queues. Required:%u, Configured:%u\n",
-			(eth_dev->data->nb_rx_queues +
-			 eth_dev->data->nb_tx_queues), enic->conf_cq_count);
+			required_cq, enic->conf_cq_count);
 		rc = -EINVAL;
 	}
 
@@ -1275,6 +1279,25 @@ static int enic_dev_init(struct enic *enic)
 		dev_err(enic, "See the ENIC PMD guide for more information.\n");
 		return -EINVAL;
 	}
+	/* Queue counts may be zeros. rte_zmalloc returns NULL in that case. */
+	enic->cq = rte_zmalloc("enic_vnic_cq", sizeof(struct vnic_cq) *
+			       enic->conf_cq_count, 8);
+	enic->rq = rte_zmalloc("enic_vnic_rq", sizeof(struct vnic_rq) *
+			       enic->conf_rq_count, 8);
+	enic->wq = rte_zmalloc("enic_vnic_wq", sizeof(struct vnic_wq) *
+			       enic->conf_wq_count, 8);
+	if (enic->conf_cq_count > 0 && enic->cq == NULL) {
+		dev_err(enic, "failed to allocate vnic_cq, aborting.\n");
+		return -1;
+	}
+	if (enic->conf_rq_count > 0 && enic->rq == NULL) {
+		dev_err(enic, "failed to allocate vnic_rq, aborting.\n");
+		return -1;
+	}
+	if (enic->conf_wq_count > 0 && enic->wq == NULL) {
+		dev_err(enic, "failed to allocate vnic_wq, aborting.\n");
+		return -1;
+	}
 
 	/* Get the supported filters */
 	enic_fdir_info(enic);
-- 
2.12.0