[PATCH] vhost: clean up outstanding buffers before setting vring
From: Shirley Ma <hidden>
Date: 2011-07-19 18:02:50
Subsystem:
the rest, virtio host (vhost) · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
The outstanding DMA buffers need to be clean up before setting vring in vhost. Otherwise the vring would be out of sync. Signed-off-by: Shirley Ma<redacted> --- drivers/vhost/vhost.c | 11 +++++++++-- 1 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index c14c42b..d6315b4 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c@@ -445,8 +445,10 @@ void vhost_dev_cleanup(struct vhost_dev *dev) vhost_poll_flush(&dev->vqs[i].poll); } /* Wait for all lower device DMAs done. */ - if (dev->vqs[i].ubufs) + if (dev->vqs[i].ubufs) { vhost_ubuf_put_and_wait(dev->vqs[i].ubufs); + kfree(dev->vqs[i].ubufs); + } /* Signal guest as appropriate. */ vhost_zerocopy_signal_used(&dev->vqs[i]);
@@ -651,6 +653,12 @@ static long vhost_set_vring(struct vhost_dev *d, int ioctl, void __user *argp) vq = d->vqs + idx; mutex_lock(&vq->mutex); + /* Wait for all lower device DMAs done. */ + if (vq->ubufs) + vhost_ubuf_put_and_wait(vq->ubufs); + + /* Signal guest as appropriate. */ + vhost_zerocopy_signal_used(vq); switch (ioctl) { case VHOST_SET_VRING_NUM:
@@ -1592,7 +1600,6 @@ void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs) { kref_put(&ubufs->kref, vhost_zerocopy_done_signal); wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount)); - kfree(ubufs); } void vhost_zerocopy_callback(void *arg)