[RFC net-next 06/18] tuntap: remove usage of ptr ring in vhost_net

From: Prashant Bhole <prashantbhole.linux@gmail.com>
To: "David S . Miller" <davem@davemloft.net>,
	"Michael S . Tsirkin" <mst@redhat.com>
Cc: Prashant Bhole <prashantbhole.linux@gmail.com>,
	Jason Wang <jasowang@redhat.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Jakub Kicinski <jakub.kicinski@netronome.com>,
	Jesper Dangaard Brouer <hawk@kernel.org>,
	John Fastabend <john.fastabend@gmail.com>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>, Andrii Nakryiko <andriin@fb.com>,
	netdev@vger.kernel.org, qemu-devel@nongnu.org,
	kvm@vger.kernel.org
Subject: [RFC net-next 06/18] tuntap: remove usage of ptr ring in vhost_net
Date: Tue, 26 Nov 2019 19:07:32 +0900	[thread overview]
Message-ID: <20191126100744.5083-7-prashantbhole.linux@gmail.com> (raw)
In-Reply-To: <20191126100744.5083-1-prashantbhole.linux@gmail.com>

Remove usage of ptr ring of tuntap in vhost_net and remove the
functions exported from tuntap drivers to get ptr ring.

Signed-off-by: Prashant Bhole <prashantbhole.linux@gmail.com>
---
 drivers/net/tap.c      | 13 -------------
 drivers/net/tun.c      | 13 -------------
 drivers/vhost/net.c    | 31 ++++---------------------------
 include/linux/if_tap.h |  5 -----
 include/linux/if_tun.h |  5 -----
 5 files changed, 4 insertions(+), 63 deletions(-)

diff --git a/drivers/net/tap.c b/drivers/net/tap.c
index 8635cdfd7aa4..6426501b8d0e 100644
--- a/drivers/net/tap.c
+++ b/drivers/net/tap.c
@@ -1298,19 +1298,6 @@ struct socket *tap_get_socket(struct file *file)
 }
 EXPORT_SYMBOL_GPL(tap_get_socket);
 
-struct ptr_ring *tap_get_ptr_ring(struct file *file)
-{
-	struct tap_queue *q;
-
-	if (file->f_op != &tap_fops)
-		return ERR_PTR(-EINVAL);
-	q = file->private_data;
-	if (!q)
-		return ERR_PTR(-EBADFD);
-	return &q->ring;
-}
-EXPORT_SYMBOL_GPL(tap_get_ptr_ring);
-
 int tap_queue_resize(struct tap_dev *tap)
 {
 	struct net_device *dev = tap->dev;
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 4f28f2387435..d078b4659897 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -3750,19 +3750,6 @@ struct socket *tun_get_socket(struct file *file)
 }
 EXPORT_SYMBOL_GPL(tun_get_socket);
 
-struct ptr_ring *tun_get_tx_ring(struct file *file)
-{
-	struct tun_file *tfile;
-
-	if (file->f_op != &tun_fops)
-		return ERR_PTR(-EINVAL);
-	tfile = file->private_data;
-	if (!tfile)
-		return ERR_PTR(-EBADFD);
-	return &tfile->tx_ring;
-}
-EXPORT_SYMBOL_GPL(tun_get_tx_ring);
-
 module_init(tun_init);
 module_exit(tun_cleanup);
 MODULE_DESCRIPTION(DRV_DESCRIPTION);
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 0f91b374a558..2e069d1ef946 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -122,7 +122,6 @@ struct vhost_net_virtqueue {
 	/* Reference counting for outstanding ubufs.
 	 * Protected by vq mutex. Writers must also take device mutex. */
 	struct vhost_net_ubuf_ref *ubufs;
-	struct ptr_ring *rx_ring;
 	struct vhost_net_buf rxq;
 	/* Batched XDP buffs */
 	struct xdp_buff *xdp;
@@ -997,8 +996,9 @@ static int peek_head_len(struct vhost_net_virtqueue *rvq, struct sock *sk)
 	int len = 0;
 	unsigned long flags;
 
-	if (rvq->rx_ring)
-		return vhost_net_buf_peek(rvq);
+	len = vhost_net_buf_peek(rvq);
+	if (len)
+		return len;
 
 	spin_lock_irqsave(&sk->sk_receive_queue.lock, flags);
 	head = skb_peek(&sk->sk_receive_queue);
@@ -1187,7 +1187,7 @@ static void handle_rx(struct vhost_net *net)
 			goto out;
 		}
 		busyloop_intr = false;
-		if (nvq->rx_ring) {
+		if (!vhost_net_buf_is_empty(&nvq->rxq)) {
 			ctl.type = TUN_MSG_PKT;
 			ctl.ptr = vhost_net_buf_consume(&nvq->rxq);
 			msg.msg_control = &ctl;
@@ -1343,7 +1343,6 @@ static int vhost_net_open(struct inode *inode, struct file *f)
 		n->vqs[i].batched_xdp = 0;
 		n->vqs[i].vhost_hlen = 0;
 		n->vqs[i].sock_hlen = 0;
-		n->vqs[i].rx_ring = NULL;
 		vhost_net_buf_init(&n->vqs[i].rxq);
 	}
 	vhost_dev_init(dev, vqs, VHOST_NET_VQ_MAX,
@@ -1372,7 +1371,6 @@ static struct socket *vhost_net_stop_vq(struct vhost_net *n,
 	vhost_net_disable_vq(n, vq);
 	vhost_net_buf_unproduce(nvq);
 	vq->private_data = NULL;
-	nvq->rx_ring = NULL;
 	mutex_unlock(&vq->mutex);
 	return sock;
 }
@@ -1468,25 +1466,6 @@ static struct socket *get_raw_socket(int fd)
 	return ERR_PTR(r);
 }
 
-static struct ptr_ring *get_tap_ptr_ring(int fd)
-{
-	struct ptr_ring *ring;
-	struct file *file = fget(fd);
-
-	if (!file)
-		return NULL;
-	ring = tun_get_tx_ring(file);
-	if (!IS_ERR(ring))
-		goto out;
-	ring = tap_get_ptr_ring(file);
-	if (!IS_ERR(ring))
-		goto out;
-	ring = NULL;
-out:
-	fput(file);
-	return ring;
-}
-
 static struct socket *get_tap_socket(int fd)
 {
 	struct file *file = fget(fd);
@@ -1570,8 +1549,6 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
 		r = vhost_net_enable_vq(n, vq);
 		if (r)
 			goto err_used;
-		if (index == VHOST_NET_VQ_RX)
-			nvq->rx_ring = get_tap_ptr_ring(fd);
 
 		oldubufs = nvq->ubufs;
 		nvq->ubufs = ubufs;
diff --git a/include/linux/if_tap.h b/include/linux/if_tap.h
index 915a187cfabd..68fe366fb185 100644
--- a/include/linux/if_tap.h
+++ b/include/linux/if_tap.h
@@ -4,7 +4,6 @@
 
 #if IS_ENABLED(CONFIG_TAP)
 struct socket *tap_get_socket(struct file *);
-struct ptr_ring *tap_get_ptr_ring(struct file *file);
 #else
 #include <linux/err.h>
 #include <linux/errno.h>
@@ -14,10 +13,6 @@ static inline struct socket *tap_get_socket(struct file *f)
 {
 	return ERR_PTR(-EINVAL);
 }
-static inline struct ptr_ring *tap_get_ptr_ring(struct file *f)
-{
-	return ERR_PTR(-EINVAL);
-}
 #endif /* CONFIG_TAP */
 
 #include <net/sock.h>
diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h
index bb94843e3829..f01a255e076d 100644
--- a/include/linux/if_tun.h
+++ b/include/linux/if_tun.h
@@ -44,7 +44,6 @@ struct tun_xdp_hdr {
 
 #if defined(CONFIG_TUN) || defined(CONFIG_TUN_MODULE)
 struct socket *tun_get_socket(struct file *);
-struct ptr_ring *tun_get_tx_ring(struct file *file);
 bool tun_is_xdp_frame(void *ptr);
 void *tun_xdp_to_ptr(void *ptr);
 void *tun_ptr_to_xdp(void *ptr);
@@ -58,10 +57,6 @@ static inline struct socket *tun_get_socket(struct file *f)
 {
 	return ERR_PTR(-EINVAL);
 }
-static inline struct ptr_ring *tun_get_tx_ring(struct file *f)
-{
-	return ERR_PTR(-EINVAL);
-}
 static inline bool tun_is_xdp_frame(void *ptr)
 {
 	return false;
-- 
2.20.1

