[PATCH v2 4/5] vhost: annotate virtqueue access checks

[David Marchand]

Modifying vq->access_ok should be done with a write lock taken.
Annotate vring_translate() and vring_invalidate().

Signed-off-by: David Marchand <david.marchand at redhat.com>
Acked-by: Eelco Chaudron <echaudro at redhat.com>
---
Changes since v1:
- moved fixes in separate patches,

---
 lib/vhost/vhost.h      | 7 +++++--
 lib/vhost/vhost_user.c | 8 ++++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
index f8624fba3d..6767246656 100644
--- a/lib/vhost/vhost.h
+++ b/lib/vhost/vhost.h
@@ -295,7 +295,8 @@ struct vhost_virtqueue {
 #define VIRTIO_UNINITIALIZED_EVENTFD	(-2)
 
 	bool			enabled;
-	bool			access_ok;
+	/* Protected by vq->access_lock */
+	bool			access_ok __rte_guarded_var;
 	bool			ready;
 
 	rte_rwlock_t		access_lock;
@@ -875,11 +876,13 @@ void *vhost_alloc_copy_ind_table(struct virtio_net *dev,
 			uint64_t desc_addr, uint64_t desc_len)
 	__rte_shared_locks_required(&vq->iotlb_lock);
 int vring_translate(struct virtio_net *dev, struct vhost_virtqueue *vq)
+	__rte_exclusive_locks_required(&vq->access_lock)
 	__rte_shared_locks_required(&vq->iotlb_lock);
 uint64_t translate_log_addr(struct virtio_net *dev, struct vhost_virtqueue *vq,
 		uint64_t log_addr)
 	__rte_shared_locks_required(&vq->iotlb_lock);
-void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq);
+void vring_invalidate(struct virtio_net *dev, struct vhost_virtqueue *vq)
+	__rte_exclusive_locks_required(&vq->access_lock);
 
 static __rte_always_inline uint64_t
 vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
index a323ce5fbf..651ea5854b 100644
--- a/lib/vhost/vhost_user.c
+++ b/lib/vhost/vhost_user.c
@@ -787,6 +787,8 @@ translate_ring_addresses(struct virtio_net **pdev, struct vhost_virtqueue **pvq)
 	dev = *pdev;
 	vq = *pvq;
 
+	vq_assert_lock(dev, vq);
+
 	if (vq->ring_addrs.flags & (1 << VHOST_VRING_F_LOG)) {
 		vq->log_guest_addr =
 			log_addr_to_gpa(dev, vq);
@@ -924,6 +926,9 @@ vhost_user_set_vring_addr(struct virtio_net **pdev,
 	/* addr->index refers to the queue index. The txq 1, rxq is 0. */
 	vq = dev->virtqueue[ctx->msg.payload.addr.index];
 
+	/* vhost_user_lock_all_queue_pairs locked all qps */
+	vq_assert_lock(dev, vq);
+
 	access_ok = vq->access_ok;
 
 	/*
@@ -1436,6 +1441,9 @@ vhost_user_set_mem_table(struct virtio_net **pdev,
 			continue;
 
 		if (vq->desc || vq->avail || vq->used) {
+			/* vhost_user_lock_all_queue_pairs locked all qps */
+			vq_assert_lock(dev, vq);
+
 			/*
 			 * If the memory table got updated, the ring addresses
 			 * need to be translated again as virtual addresses have
-- 
2.42.0