[PATCH 3/3] vhost: annotate virtqueue access checks

[David Marchand <david.marchand@redhat.com>]

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

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/vhost/vduse.c      |  4 ++++
 lib/vhost/vhost.h      |  7 +++++--
 lib/vhost/vhost_user.c | 10 ++++++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
index 080b58f7de..e198eeef64 100644
--- a/lib/vhost/vduse.c
+++ b/lib/vhost/vduse.c
@@ -196,6 +196,7 @@ vduse_vring_setup(struct virtio_net *dev, unsigned int index)
 				vq->size * sizeof(struct batch_copy_elem),
 				RTE_CACHE_LINE_SIZE, 0);
 
+	rte_rwlock_write_lock(&vq->access_lock);
 	vhost_user_iotlb_rd_lock(vq);
 	if (vring_translate(dev, vq))
 		VHOST_LOG_CONFIG(dev->ifname, ERR, "Failed to translate vring %d addresses\n",
@@ -206,6 +207,7 @@ vduse_vring_setup(struct virtio_net *dev, unsigned int index)
 				"Failed to disable guest notifications on vring %d\n",
 				index);
 	vhost_user_iotlb_rd_unlock(vq);
+	rte_rwlock_write_unlock(&vq->access_lock);
 
 	vq_efd.index = index;
 	vq_efd.fd = vq->kickfd;
@@ -259,7 +261,9 @@ vduse_vring_cleanup(struct virtio_net *dev, unsigned int index)
 	close(vq->kickfd);
 	vq->kickfd = VIRTIO_UNINITIALIZED_EVENTFD;
 
+	rte_rwlock_write_lock(&vq->access_lock);
 	vring_invalidate(dev, vq);
+	rte_rwlock_write_unlock(&vq->access_lock);
 
 	rte_free(vq->batch_copy_elems);
 	vq->batch_copy_elems = NULL;
diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
index 5fc9035a1f..70d18bdfbf 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;
@@ -874,11 +875,13 @@ 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 5bbdbd54d8..cbe2222ef3 100644
--- a/lib/vhost/vhost_user.c
+++ b/lib/vhost/vhost_user.c
@@ -797,6 +797,8 @@ 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);
@@ -934,6 +936,9 @@ 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 */
+	VHOST_USER_ASSERT_LOCK(dev, vq, VHOST_USER_SET_VRING_ADDR);
+
 	access_ok = vq->access_ok;
 
 	/*
@@ -1446,6 +1451,9 @@ 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 */
+			VHOST_USER_ASSERT_LOCK(dev, vq, VHOST_USER_SET_MEM_TABLE);
+
 			/*
 			 * If the memory table got updated, the ring addresses
 			 * need to be translated again as virtual addresses have
@@ -2208,7 +2216,9 @@ vhost_user_get_vring_base(struct virtio_net **pdev,
 
 	vhost_user_iotlb_flush_all(dev);
 
+	rte_rwlock_write_lock(&vq->access_lock);
 	vring_invalidate(dev, vq);
+	rte_rwlock_write_unlock(&vq->access_lock);
 
 	return RTE_VHOST_MSG_RESULT_REPLY;
 }
-- 
2.41.0