From 2256e8482b2bba88abcc734dbc6951b825773f0b Mon Sep 17 00:00:00 2001 From: Jonah Palmer Date: Wed, 10 Jul 2024 08:55:15 -0400 Subject: [PATCH] virtio: virtqueue_pop - VIRTIO_F_IN_ORDER support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add VIRTIO_F_IN_ORDER feature support in virtqueue_split_pop and virtqueue_packed_pop. VirtQueueElements popped from the available/descritpor ring are added to the VirtQueue's used_elems array in-order and in the same fashion as they would be added the used and descriptor rings, respectively. This will allow us to keep track of the current order, what elements have been written, as well as an element's essential data after being processed. Reviewed-by: Eugenio Pérez Signed-off-by: Jonah Palmer Message-Id: <20240710125522.4168043-3-jonah.palmer@oracle.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 583a224163..98eb601b09 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -1505,7 +1505,7 @@ static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_nu static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) { - unsigned int i, head, max; + unsigned int i, head, max, idx; VRingMemoryRegionCaches *caches; MemoryRegionCache indirect_desc_cache; MemoryRegionCache *desc_cache; @@ -1629,6 +1629,13 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz) elem->in_sg[i] = iov[out_num + i]; } + if (virtio_vdev_has_feature(vdev, VIRTIO_F_IN_ORDER)) { + idx = (vq->last_avail_idx - 1) % vq->vring.num; + vq->used_elems[idx].index = elem->index; + vq->used_elems[idx].len = elem->len; + vq->used_elems[idx].ndescs = elem->ndescs; + } + vq->inuse++; trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num); @@ -1762,6 +1769,13 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz) elem->index = id; elem->ndescs = (desc_cache == &indirect_desc_cache) ? 1 : elem_entries; + + if (virtio_vdev_has_feature(vdev, VIRTIO_F_IN_ORDER)) { + vq->used_elems[vq->last_avail_idx].index = elem->index; + vq->used_elems[vq->last_avail_idx].len = elem->len; + vq->used_elems[vq->last_avail_idx].ndescs = elem->ndescs; + } + vq->last_avail_idx += elem->ndescs; vq->inuse += elem->ndescs;