[dpdk-dev] [PATCH v3 2/2] virtio: fix memory leak of virtqueue memzones

[Jianfeng Tan]

Issue: When virtio was proposed in DPDK, there is no API to free memzones.
But this has changed since rte_memzone_free() has been implemented by
commit ff909fe21f0a ("mem: introduce memzone freeing").

This patch is to make sure memzones in struct virtqueue, like mz and
virtio_net_hdr_mz, are freed when queue is released or setup fails.

Signed-off-by: Jianfeng Tan <jianfeng.tan at intel.com>
---
 drivers/net/virtio/virtio_ethdev.c | 21 ++++++++++++++-------
 drivers/net/virtio/virtqueue.h     |  2 ++
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c 
b/drivers/net/virtio/virtio_ethdev.c
index b3f4158..bd990ff 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -260,12 +260,18 @@ virtio_set_multiple_queues(struct rte_eth_dev *dev, 
uint16_t nb_queues)
 }

 void
-virtio_dev_queue_release(struct virtqueue *vq) {
+virtio_dev_queue_release(struct virtqueue *vq)
+{
        struct virtio_hw *hw;

        if (vq) {
                hw = vq->hw;
-               hw->vtpci_ops->del_queue(hw, vq);
+               if (vq->started)
+                       hw->vtpci_ops->del_queue(hw, vq);
+
+               rte_memzone_free(vq->mz);
+               if (vq->virtio_net_hdr_mz)
+                       rte_memzone_free(vq->virtio_net_hdr_mz);

                rte_free(vq->sw_ring);
                rte_free(vq);
@@ -330,7 +336,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
                                                 socket_id);
                if (!vq->sw_ring) {
                        PMD_INIT_LOG(ERR, "Can not allocate RX soft ring");
-                       rte_free(vq);
+                       virtio_dev_queue_release(vq);
                        return -ENOMEM;
                }
        }
@@ -358,7 +364,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
                if (rte_errno == EEXIST)
                        mz = rte_memzone_lookup(vq_name);
                if (mz == NULL) {
-                       rte_free(vq);
+                       virtio_dev_queue_release(vq);
                        return -ENOMEM;
                }
        }
@@ -370,7 +376,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
         */
        if ((mz->phys_addr + vq->vq_ring_size - 1) >> 
(VIRTIO_PCI_QUEUE_ADDR_SHIFT + 32)) {
                PMD_INIT_LOG(ERR, "vring address shouldn't be above 16TB!");
-               rte_free(vq);
+               virtio_dev_queue_release(vq);
                return -ENOMEM;
        }

@@ -402,7 +408,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
                        if (rte_errno == EEXIST)
                                hdr_mz = rte_memzone_lookup(vq_name);
                        if (hdr_mz == NULL) {
-                               rte_free(vq);
+                               virtio_dev_queue_release(vq);
                                return -ENOMEM;
                        }
                }
@@ -436,7 +442,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,
                                vq->virtio_net_hdr_mz =
                                        rte_memzone_lookup(vq_name);
                        if (vq->virtio_net_hdr_mz == NULL) {
-                               rte_free(vq);
+                               virtio_dev_queue_release(vq);
                                return -ENOMEM;
                        }
                }
@@ -447,6 +453,7 @@ int virtio_dev_queue_setup(struct rte_eth_dev *dev,

        hw->vtpci_ops->setup_queue(hw, vq);

+       vq->started = 1;
        *pvq = vq;
        return 0;
 }
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index 4e9239e..83d89ca 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -201,6 +201,8 @@ struct virtqueue {

        uint16_t        *notify_addr;

+       int             started;
+
        struct vq_desc_extra {
                void              *cookie;
                uint16_t          ndescs;
-- 
2.1.4