From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:46563) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1glrU7-0000EW-A6 for qemu-devel@nongnu.org; Tue, 22 Jan 2019 03:32:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1glrU5-0002g6-IY for qemu-devel@nongnu.org; Tue, 22 Jan 2019 03:32:39 -0500 Received: from mail-pl1-x642.google.com ([2607:f8b0:4864:20::642]:39038) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1glrU5-0002cz-Ap for qemu-devel@nongnu.org; Tue, 22 Jan 2019 03:32:37 -0500 Received: by mail-pl1-x642.google.com with SMTP id 101so11102632pld.6 for ; Tue, 22 Jan 2019 00:32:31 -0800 (PST) From: elohimes@gmail.com Date: Tue, 22 Jan 2019 16:31:48 +0800 Message-Id: <20190122083152.10705-3-xieyongji@baidu.com> In-Reply-To: <20190122083152.10705-1-xieyongji@baidu.com> References: <20190122083152.10705-1-xieyongji@baidu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v5 2/6] libvhost-user: Introduce vu_queue_map_desc() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: mst@redhat.com, stefanha@gmail.com, marcandre.lureau@redhat.com, berrange@redhat.com, jasowang@redhat.com, maxime.coquelin@redhat.com, yury-kotov@yandex-team.ru, wrfsh@yandex-team.ru Cc: qemu-devel@nongnu.org, zhangyu31@baidu.com, chaiwen@baidu.com, nixun@baidu.com, lilin24@baidu.com, Xie Yongji From: Xie Yongji Introduce vu_queue_map_desc() which should be independent with vu_queue_pop(); Signed-off-by: Xie Yongji Signed-off-by: Zhang Yu Reviewed-by: Marc-André Lureau --- contrib/libvhost-user/libvhost-user.c | 88 ++++++++++++++++----------- 1 file changed, 51 insertions(+), 37 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index a6b46cdc03..23bd52264c 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -1853,49 +1853,20 @@ virtqueue_alloc_element(size_t sz, return elem; } -void * -vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) +static void * +vu_queue_map_desc(VuDev *dev, VuVirtq *vq, unsigned int idx, size_t sz) { - unsigned int i, head, max, desc_len; + struct vring_desc *desc = vq->vring.desc; uint64_t desc_addr, read_len; + unsigned int desc_len; + unsigned int max = vq->vring.num; + unsigned int i = idx; VuVirtqElement *elem; - unsigned out_num, in_num; + unsigned int out_num = 0, in_num = 0; struct iovec iov[VIRTQUEUE_MAX_SIZE]; struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; - struct vring_desc *desc; int rc; - if (unlikely(dev->broken) || - unlikely(!vq->vring.avail)) { - return NULL; - } - - if (vu_queue_empty(dev, vq)) { - return NULL; - } - /* Needed after virtio_queue_empty(), see comment in - * virtqueue_num_heads(). */ - smp_rmb(); - - /* When we start there are none of either input nor output. */ - out_num = in_num = 0; - - max = vq->vring.num; - if (vq->inuse >= vq->vring.num) { - vu_panic(dev, "Virtqueue size exceeded"); - return NULL; - } - - if (!virtqueue_get_head(dev, vq, vq->last_avail_idx++, &head)) { - return NULL; - } - - if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { - vring_set_avail_event(vq, vq->last_avail_idx); - } - - i = head; - desc = vq->vring.desc; if (desc[i].flags & VRING_DESC_F_INDIRECT) { if (desc[i].len % sizeof(struct vring_desc)) { vu_panic(dev, "Invalid size for indirect buffer table"); @@ -1947,12 +1918,13 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) } while (rc == VIRTQUEUE_READ_DESC_MORE); if (rc == VIRTQUEUE_READ_DESC_ERROR) { + vu_panic(dev, "read descriptor error"); return NULL; } /* Now copy what we have collected and mapped */ elem = virtqueue_alloc_element(sz, out_num, in_num); - elem->index = head; + elem->index = idx; for (i = 0; i < out_num; i++) { elem->out_sg[i] = iov[i]; } @@ -1960,6 +1932,48 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) elem->in_sg[i] = iov[out_num + i]; } + return elem; +} + +void * +vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) +{ + unsigned int head; + VuVirtqElement *elem; + + if (unlikely(dev->broken) || + unlikely(!vq->vring.avail)) { + return NULL; + } + + if (vu_queue_empty(dev, vq)) { + return NULL; + } + /* + * Needed after virtio_queue_empty(), see comment in + * virtqueue_num_heads(). + */ + smp_rmb(); + + if (vq->inuse >= vq->vring.num) { + vu_panic(dev, "Virtqueue size exceeded"); + return NULL; + } + + if (!virtqueue_get_head(dev, vq, vq->last_avail_idx++, &head)) { + return NULL; + } + + if (vu_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) { + vring_set_avail_event(vq, vq->last_avail_idx); + } + + elem = vu_queue_map_desc(dev, vq, head, sz); + + if (!elem) { + return NULL; + } + vq->inuse++; return elem; -- 2.17.1