[v6 1/5] vhost: skip crypto op fetch before vring init

[Gowrishankar Muthukrishnan <gmuthukrishn@marvell.com>]

Until virtio avail ring is initialized (by VHOST_USER_SET_VRING_ADDR),
worker thread should not try to fetch crypto op, which would lead to
memory fault.

Fixes: 939066d96563 ("vhost/crypto: add public function implementation")
Cc: stable@dpdk.org

Signed-off-by: Gowrishankar Muthukrishnan <gmuthukrishn@marvell.com>
Acked-by: Akhil Goyal <gakhil@marvell.com>
---
v6:
 - added lock checks.
---
 lib/vhost/vhost_crypto.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/lib/vhost/vhost_crypto.c b/lib/vhost/vhost_crypto.c
index 3dc41a3bd5..d3d13eff07 100644
--- a/lib/vhost/vhost_crypto.c
+++ b/lib/vhost/vhost_crypto.c
@@ -8,6 +8,7 @@
 #include <rte_mbuf.h>
 #include <rte_cryptodev.h>
 
+#include "iotlb.h"
 #include "rte_vhost_crypto.h"
 #include "vhost.h"
 #include "vhost_user.h"
@@ -1580,7 +1581,26 @@ rte_vhost_crypto_fetch_requests(int vid, uint32_t qid,
 
 	vq = dev->virtqueue[qid];
 
+	if (unlikely(vq == NULL)) {
+		VC_LOG_ERR("Invalid virtqueue %u", qid);
+		return 0;
+	}
+
+	if (unlikely(rte_rwlock_read_trylock(&vq->access_lock) != 0))
+		return 0;
+
+	vhost_user_iotlb_rd_lock(vq);
+	if (unlikely(!vq->access_ok)) {
+		VC_LOG_DBG("Virtqueue %u vrings not yet initialized", qid);
+		vhost_user_iotlb_rd_unlock(vq);
+		rte_rwlock_read_unlock(&vq->access_lock);
+		return 0;
+	}
+
 	avail_idx = *((volatile uint16_t *)&vq->avail->idx);
+	vhost_user_iotlb_rd_unlock(vq);
+	rte_rwlock_read_unlock(&vq->access_lock);
+
 	start_idx = vq->last_used_idx;
 	count = avail_idx - start_idx;
 	count = RTE_MIN(count, VHOST_CRYPTO_MAX_BURST_SIZE);
-- 
2.25.1