From 160cbc815b41f45af826136785806c887a7851a1 Mon Sep 17 00:00:00 2001 From: Yuanhan Liu Date: Thu, 2 Mar 2017 14:16:07 +0800 Subject: [PATCH] vhost: remove a hack on queue allocation We used to allocate queues based on the index from SET_VRING_CALL request: if corresponding queue hasn't been allocated, allocate it. Though it's pratically right (it's the first per-vring request we will get from QEMU for vhost-user negotiation), but it's not technically right: it's not documented in the vhost-user spec that it will always be the first per-vring request. For example, SET_VRING_ADDR could also be the first per-vring request. Thus, we should not depend the SET_VRING_CALL on queue allocation. Instead, we could catch all the per-vring messages at the entrance of request handler, and allocate one if it hasn't been allocated before. By that, we could remove a hack. Signed-off-by: Yuanhan Liu --- lib/librte_vhost/vhost_user.c | 61 +++++++++++++++++++++++++++-------- 1 file changed, 48 insertions(+), 13 deletions(-) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index cb2156af36..2767cca1ad 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -635,7 +635,6 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg) { struct vhost_vring_file file; struct vhost_virtqueue *vq; - uint32_t cur_qp_idx; file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) @@ -645,19 +644,7 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg) RTE_LOG(INFO, VHOST_CONFIG, "vring call idx:%d file:%d\n", file.index, file.fd); - /* - * FIXME: VHOST_SET_VRING_CALL is the first per-vring message - * we get, so we do vring queue pair allocation here. - */ - cur_qp_idx = file.index / VIRTIO_QNUM; - if (cur_qp_idx + 1 > dev->virt_qp_nb) { - if (alloc_vring_queue_pair(dev, cur_qp_idx) < 0) - return; - } - vq = dev->virtqueue[file.index]; - assert(vq != NULL); - if (vq->callfd >= 0) close(vq->callfd); @@ -914,6 +901,46 @@ send_vhost_message(int sockfd, struct VhostUserMsg *msg) return ret; } +/* + * Allocate a queue pair if it hasn't been allocated yet + */ +static int +vhost_user_check_and_alloc_queue_pair(struct virtio_net *dev, VhostUserMsg *msg) +{ + uint16_t vring_idx; + uint16_t qp_idx; + + switch (msg->request) { + case VHOST_USER_SET_VRING_KICK: + case VHOST_USER_SET_VRING_CALL: + case VHOST_USER_SET_VRING_ERR: + vring_idx = msg->payload.u64 & VHOST_USER_VRING_IDX_MASK; + break; + case VHOST_USER_SET_VRING_NUM: + case VHOST_USER_SET_VRING_BASE: + case VHOST_USER_SET_VRING_ENABLE: + vring_idx = msg->payload.state.index; + break; + case VHOST_USER_SET_VRING_ADDR: + vring_idx = msg->payload.addr.index; + break; + default: + return 0; + } + + qp_idx = vring_idx / VIRTIO_QNUM; + if (qp_idx >= VHOST_MAX_QUEUE_PAIRS) { + RTE_LOG(ERR, VHOST_CONFIG, + "invalid vring index: %u\n", vring_idx); + return -1; + } + + if (dev->virtqueue[qp_idx * VIRTIO_QNUM]) + return 0; + + return alloc_vring_queue_pair(dev, qp_idx); +} + int vhost_user_msg_handler(int vid, int fd) { @@ -943,6 +970,14 @@ vhost_user_msg_handler(int vid, int fd) ret = 0; RTE_LOG(INFO, VHOST_CONFIG, "read message %s\n", vhost_message_str[msg.request]); + + ret = vhost_user_check_and_alloc_queue_pair(dev, &msg); + if (ret < 0) { + RTE_LOG(ERR, VHOST_CONFIG, + "failed to alloc queue\n"); + return -1; + } + switch (msg.request) { case VHOST_USER_GET_FEATURES: msg.payload.u64 = vhost_user_get_features(); -- 2.20.1