From 24b8cf88f53f9fc7cb393c9cad908f759980bfee Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Eugenio=20P=C3=A9rez?= Date: Thu, 21 Jul 2022 15:38:55 +0200 Subject: [PATCH 16/32] vhost: Track number of descs in SVQDescState MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Eugenio Pérez RH-MergeRequest: 108: Net Control Virtqueue shadow Support RH-Commit: [16/27] 26f30cb6dd35c1eb1ddabe25113431bed3d744aa (eperezmartin/qemu-kvm) RH-Bugzilla: 1939363 RH-Acked-by: Stefano Garzarella RH-Acked-by: Cindy Lu RH-Acked-by: Laurent Vivier Bugzilla: https://bugzilla.redhat.com/1939363 Upstream Status: git://git.qemu.org/qemu.git commit ac4cfdc6f39c06732d27554523f9d5f8a53b4ffa Author: Eugenio Pérez Date: Wed Jul 20 08:59:35 2022 +0200 vhost: Track number of descs in SVQDescState A guest's buffer continuos on GPA may need multiple descriptors on qemu's VA, so SVQ should track its length sepparatedly. Signed-off-by: Eugenio Pérez Reviewed-by: Michael S. Tsirkin Signed-off-by: Jason Wang Signed-off-by: Eugenio Pérez --- hw/virtio/vhost-shadow-virtqueue.c | 4 ++-- hw/virtio/vhost-shadow-virtqueue.h | 6 ++++++ 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c index a08e3d4025..4d99075e73 100644 --- a/hw/virtio/vhost-shadow-virtqueue.c +++ b/hw/virtio/vhost-shadow-virtqueue.c @@ -257,6 +257,7 @@ static int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg, } svq->desc_state[qemu_head].elem = elem; + svq->desc_state[qemu_head].ndescs = ndescs; vhost_svq_kick(svq); return 0; } @@ -418,8 +419,7 @@ static VirtQueueElement *vhost_svq_get_buf(VhostShadowVirtqueue *svq, return NULL; } - num = svq->desc_state[used_elem.id].elem->in_num + - svq->desc_state[used_elem.id].elem->out_num; + num = svq->desc_state[used_elem.id].ndescs; 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; diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h index d646c35054..5c7e7cbab6 100644 --- a/hw/virtio/vhost-shadow-virtqueue.h +++ b/hw/virtio/vhost-shadow-virtqueue.h @@ -17,6 +17,12 @@ typedef struct SVQDescState { VirtQueueElement *elem; + + /* + * Number of descriptors exposed to the device. May or may not match + * guest's + */ + unsigned int ndescs; } SVQDescState; /* Shadow virtqueue to relay notifications */ -- 2.31.1