linux-kernel - [PATCH V3 08/15] vhost_net: switch to use shadow used ring API for RX

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 17 Jul 2019 06:52:48 -0400
From:   Jason Wang <jasowang@...hat.com>
To:     mst@...hat.com, jasowang@...hat.com
Cc:     kvm@...r.kernel.org, virtualization@...ts.linux-foundation.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        jfreimann@...hat.com, tiwei.bie@...el.com,
        maxime.coquelin@...hat.com
Subject: [PATCH V3 08/15] vhost_net: switch to use shadow used ring API for RX

This patch switches to use shadow used ring API for RX. This will help
to hid used ring layout from device.

Signed-off-by: Jason Wang <jasowang@...hat.com>
---
 drivers/vhost/net.c | 37 +++++++++++--------------------------
 1 file changed, 11 insertions(+), 26 deletions(-)

diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 1a67f889cbc1..9e087d08b199 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -445,18 +445,6 @@ static int vhost_net_enable_vq(struct vhost_net *n,
 	return vhost_poll_start(poll, sock->file);
 }
 
-static void vhost_net_signal_used(struct vhost_net_virtqueue *nvq)
-{
-	struct vhost_virtqueue *vq = &nvq->vq;
-	struct vhost_dev *dev = vq->dev;
-
-	if (!nvq->done_idx)
-		return;
-
-	vhost_add_used_and_signal_n(dev, vq, vq->heads, nvq->done_idx);
-	nvq->done_idx = 0;
-}
-
 static void vhost_tx_batch(struct vhost_net *net,
 			   struct vhost_net_virtqueue *nvq,
 			   struct socket *sock,
@@ -999,7 +987,7 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk,
 
 	if (!len && rvq->busyloop_timeout) {
 		/* Flush batched heads first */
-		vhost_net_signal_used(rnvq);
+		vhost_flush_shadow_used_and_signal(rvq);
 		/* Both tx vq and rx socket were polled here */
 		vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, true);
 
@@ -1020,7 +1008,6 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk,
  *	returns number of buffer heads allocated, negative on error
  */
 static int get_rx_bufs(struct vhost_virtqueue *vq,
-		       struct vring_used_elem *heads,
 		       int datalen,
 		       unsigned *iovcount,
 		       struct vhost_log *log,
@@ -1063,11 +1050,11 @@ static int get_rx_bufs(struct vhost_virtqueue *vq,
 			nlogs += *log_num;
 			log += *log_num;
 		}
-		heads[headcount].id = cpu_to_vhost32(vq, d);
 		len = iov_length(vq->iov + seg, in);
 		datalen -= len;
-		heads[headcount].len = cpu_to_vhost32(vq,
-				       datalen >= 0 ? len : len + datalen);
+		vhost_add_shadow_used(vq, cpu_to_vhost32(vq, d),
+				      cpu_to_vhost32(vq, datalen >= 0 ? len
+						     : len + datalen));
 		++headcount;
 		seg += in;
 	}
@@ -1082,7 +1069,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq,
 	}
 	return headcount;
 err:
-	vhost_discard_vq_desc(vq, headcount);
+	vhost_discard_shadow_used(vq, headcount);
 	return r;
 }
 
@@ -1141,8 +1128,7 @@ static void handle_rx(struct vhost_net *net)
 			break;
 		sock_len += sock_hlen;
 		vhost_len = sock_len + vhost_hlen;
-		headcount = get_rx_bufs(vq, vq->heads + nvq->done_idx,
-					vhost_len, &in, vq_log, &log,
+		headcount = get_rx_bufs(vq, vhost_len, &in, vq_log, &log,
 					likely(mergeable) ? UIO_MAXIOV : 1);
 		/* On error, stop handling until the next kick. */
 		if (unlikely(headcount < 0))
@@ -1189,7 +1175,7 @@ static void handle_rx(struct vhost_net *net)
 		if (unlikely(err != sock_len)) {
 			pr_debug("Discarded rx packet: "
 				 " len %d, expected %zd\n", err, sock_len);
-			vhost_discard_vq_desc(vq, headcount);
+			vhost_discard_shadow_used(vq, headcount);
 			continue;
 		}
 		/* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */
@@ -1213,12 +1199,11 @@ static void handle_rx(struct vhost_net *net)
 		    copy_to_iter(&num_buffers, sizeof num_buffers,
 				 &fixup) != sizeof num_buffers) {
 			vq_err(vq, "Failed num_buffers write");
-			vhost_discard_vq_desc(vq, headcount);
+			vhost_discard_shadow_used(vq, headcount);
 			goto out;
 		}
-		nvq->done_idx += headcount;
-		if (nvq->done_idx > VHOST_NET_BATCH)
-			vhost_net_signal_used(nvq);
+		if (vhost_get_shadow_used_count(vq) > VHOST_NET_BATCH)
+			vhost_flush_shadow_used_and_signal(vq);
 		if (unlikely(vq_log))
 			vhost_log_write(vq, vq_log, log, vhost_len,
 					vq->iov, in);
@@ -1230,7 +1215,7 @@ static void handle_rx(struct vhost_net *net)
 	else if (!sock_len)
 		vhost_net_enable_vq(net, vq);
 out:
-	vhost_net_signal_used(nvq);
+	vhost_flush_shadow_used_and_signal(vq);
 	mutex_unlock(&vq->mutex);
 }
 
-- 
2.18.1