OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

vhost: Fix device's used descriptor dequeue

Browse Source 
Only the first one of them were properly enqueued back.

Fixes: 100890f7ca ("vhost: Shadow virtqueue buffers forwarding")

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20220512175747.142058-3-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Eugenio Pérez 2022-05-12 19:57:43 +02:00 committed by Michael S. Tsirkin
parent 495fe3a787
commit 81abfa5724
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
hw/virtio/vhost-shadow-virtqueue.c
View File

@ -334,12 +334,22 @@ static void vhost_svq_disable_notification(VhostShadowVirtqueue *svq)
svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT);
}
static uint16_t vhost_svq_last_desc_of_chain(const VhostShadowVirtqueue *svq,
uint16_t num, uint16_t i)
{
for (uint16_t j = 0; j < (num - 1); ++j) {
i = le16_to_cpu(svq->desc_next[i]);
}
return i;
}
static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq,
uint32_t *len)
{
const vring_used_t *used = svq->vring.used;
vring_used_elem_t used_elem;
uint16_t last_used;
uint16_t last_used, last_used_chain, num;
if (!vhost_svq_more_used(svq)) {
return NULL;
@ -365,7 +375,10 @@ static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq,
return NULL;
}
svq->desc_next[used_elem.id] = svq->free_head;
num = svq->ring_id_maps[used_elem.id]->in_num +
svq->ring_id_maps[used_elem.id]->out_num;
last_used_chain = vhost_svq_last_desc_of_chain(svq, num, used_elem.id);
svq->desc_next[last_used_chain] = svq->free_head;
svq->free_head = used_elem.id;
*len = used_elem.len;