From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: passt.top; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=IVfVZsn3; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by passt.top (Postfix) with ESMTPS id C56DF5A0269 for ; Fri, 27 Feb 2026 15:03:48 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1772201027; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hc9I76YIX6ckCaOFaxlIzPksK4pPbRRxfoGViL8UBSg=; b=IVfVZsn3NZsD7/kFPvpnj+eoAxtaSv6Yxv9r5dChUElXyaennzNeg6VWyTerBoiYYbCQQk +ZtJaUJB1MRF6XxiOxFXxnZDaEfQhwzlKuiAWMI1ULVbZhHq68gA4qSLQflg2jp38PBMLp vHBIGZmEEVpRQNmQKliO9VRQCwisvJI= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-440-w1fa1MTjOJyWd8KuXyaHIA-1; Fri, 27 Feb 2026 09:03:45 -0500 X-MC-Unique: w1fa1MTjOJyWd8KuXyaHIA-1 X-Mimecast-MFC-AGG-ID: w1fa1MTjOJyWd8KuXyaHIA_1772201025 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E1C0F1956060 for ; Fri, 27 Feb 2026 14:03:44 +0000 (UTC) Received: from lenovo-t14s.redhat.com (unknown [10.45.225.86]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E059130001B9; Fri, 27 Feb 2026 14:03:43 +0000 (UTC) From: Laurent Vivier To: passt-dev@passt.top Subject: [PATCH 08/12] vu_common: Pass iov_tail to vu_set_vnethdr() Date: Fri, 27 Feb 2026 15:03:26 +0100 Message-ID: <20260227140330.2216753-9-lvivier@redhat.com> In-Reply-To: <20260227140330.2216753-1-lvivier@redhat.com> References: <20260227140330.2216753-1-lvivier@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 1y67fn2ZsV4HI1ciT95zyyCTHhR3-tuQDkXzrjTG9O4_1772201025 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Message-ID-Hash: S2KVVLVQS3JIRSYUESBYCWZW4KF5ST7P X-Message-ID-Hash: S2KVVLVQS3JIRSYUESBYCWZW4KF5ST7P X-MailFrom: lvivier@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Laurent Vivier X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Refactor vu_set_vnethdr() to take an iov_tail pointer instead of a direct pointer to the virtio_net_hdr_mrg_rxbuf structure. This makes the function use IOV_PEEK_HEADER() and IOV_PUT_HEADER() to read and write the virtio-net header through the iov_tail abstraction. Signed-off-by: Laurent Vivier --- tcp_vu.c | 8 +++++--- udp_vu.c | 3 +-- vu_common.c | 24 ++++++++++++++++-------- vu_common.h | 3 +-- 4 files changed, 23 insertions(+), 15 deletions(-) diff --git a/tcp_vu.c b/tcp_vu.c index 98e5974fee0e..92667507ac9b 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -94,10 +94,11 @@ int tcp_vu_send_flag(const struct ctx *c, struct tcp_tap_conn *conn, int flags) if (elem_cnt != 1) return -1; - ASSERT(flags_elem[0].in_sg[0].iov_len >= + payload = IOV_TAIL(&flags_elem[0].in_sg[0], elem_cnt, 0); + ASSERT(iov_tail_size(&payload) >= MAX(hdrlen + sizeof(*opts), ETH_ZLEN + VNET_HLEN)); - vu_set_vnethdr(vdev, flags_elem[0].in_sg[0].iov_base, 1); + vu_set_vnethdr(vdev, &payload, 1); eh = vu_eth(flags_elem[0].in_sg[0].iov_base); @@ -448,11 +449,12 @@ int tcp_vu_data_from_sock(const struct ctx *c, struct tcp_tap_conn *conn) for (i = 0, previous_dlen = -1, check = NULL; i < head_cnt; i++) { struct iovec *iov = &elem[head[i]].in_sg[0]; int buf_cnt = head[i + 1] - head[i]; + struct iov_tail data = IOV_TAIL(iov, buf_cnt, 0); ssize_t dlen = iov_size(iov, buf_cnt) - hdrlen; bool push = i == head_cnt - 1; size_t l2len; - vu_set_vnethdr(vdev, iov->iov_base, buf_cnt); + vu_set_vnethdr(vdev, &data, buf_cnt); /* The IPv4 header checksum varies only with dlen */ if (previous_dlen != dlen) diff --git a/udp_vu.c b/udp_vu.c index 6d87f4872268..5ae79b9bb0c5 100644 --- a/udp_vu.c +++ b/udp_vu.c @@ -234,8 +234,7 @@ void udp_vu_sock_to_tap(const struct ctx *c, int s, int n, flow_sidx_t tosidx) vu_queue_rewind(vq, elem_cnt - elem_used); if (data.cnt > 0) { - vu_set_vnethdr(vdev, data.iov[0].iov_base, elem_used); - iov_drop_header(&data, VNET_HLEN); + vu_set_vnethdr(vdev, &data, elem_used); udp_vu_prepare(c, &data, toside); if (*c->pcap) { udp_vu_csum(toside, &data); diff --git a/vu_common.c b/vu_common.c index 7a8cd18f4e81..a8d5fcdaea83 100644 --- a/vu_common.c +++ b/vu_common.c @@ -120,18 +120,25 @@ int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq, } /** - * vu_set_vnethdr() - set virtio-net headers + * vu_set_vnethdr() - set virtio-net header * @vdev: vhost-user device - * @vnethdr: Address of the header to set + * @data: IOV tail to write header to, updated to + * point after the virtio-net header * @num_buffers: Number of guest buffers of the frame */ -void vu_set_vnethdr(const struct vu_dev *vdev, - struct virtio_net_hdr_mrg_rxbuf *vnethdr, +void vu_set_vnethdr(const struct vu_dev *vdev, struct iov_tail *data, int num_buffers) { + struct virtio_net_hdr_mrg_rxbuf vnethdr_storage, *vnethdr; + + vnethdr = IOV_PEEK_HEADER(data, vnethdr_storage); + vnethdr->hdr = VU_HEADER; + if (vu_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) vnethdr->num_buffers = htole16(num_buffers); + + IOV_PUT_HEADER(data, vnethdr); } /** @@ -248,6 +255,7 @@ int vu_send_single(const struct ctx *c, const void *buf, size_t size) struct vu_virtq *vq = &vdev->vq[VHOST_USER_RX_QUEUE]; struct vu_virtq_element elem[VIRTQUEUE_MAX_SIZE]; struct iovec in_sg[VIRTQUEUE_MAX_SIZE]; + struct iov_tail data; size_t total; int elem_cnt; int i; @@ -269,15 +277,15 @@ int vu_send_single(const struct ctx *c, const void *buf, size_t size) goto err; } - vu_set_vnethdr(vdev, in_sg[0].iov_base, elem_cnt); - + data = IOV_TAIL(&in_sg[0], elem_cnt, 0); + vu_set_vnethdr(vdev, &data, elem_cnt); total -= VNET_HLEN; /* copy data from the buffer to the iovec */ - iov_from_buf(in_sg, elem_cnt, VNET_HLEN, buf, total); + iov_from_buf(data.iov, data.cnt, data.off, buf, total); if (*c->pcap) - pcap_iov(in_sg, elem_cnt, VNET_HLEN); + pcap_iov(data.iov, data.cnt, data.off); vu_flush(vdev, vq, elem, elem_cnt); diff --git a/vu_common.h b/vu_common.h index 052aff710502..41cf18936300 100644 --- a/vu_common.h +++ b/vu_common.h @@ -49,8 +49,7 @@ void vu_init_elem(struct vu_virtq_element *elem, struct iovec *iov, int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq, struct vu_virtq_element *elem, int max_elem, size_t size, size_t *collected); -void vu_set_vnethdr(const struct vu_dev *vdev, - struct virtio_net_hdr_mrg_rxbuf *vnethdr, +void vu_set_vnethdr(const struct vu_dev *vdev, struct iov_tail *data, int num_buffers); void vu_flush(const struct vu_dev *vdev, struct vu_virtq *vq, struct vu_virtq_element *elem, int elem_cnt); -- 2.53.0