From 1ffcbc8537d0bc32aaca7000cb9c904ec4b6300f Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Tue, 17 Apr 2018 16:45:47 +0200 Subject: tun: convert to use generic xdp_frame and xdp_return_frame API The tuntap driver invented it's own driver specific way of queuing XDP packets, by storing the xdp_buff information in the top of the XDP frame data. Convert it over to use the more generic xdp_frame structure. The main problem with the in-driver method is that the xdp_rxq_info pointer cannot be trused/used when dequeueing the frame. V3: Remove check based on feedback from Jason Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- drivers/net/tun.c | 43 ++++++++++++++++++++----------------------- drivers/vhost/net.c | 7 ++++--- 2 files changed, 24 insertions(+), 26 deletions(-) (limited to 'drivers') diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 28583aa0c17d..2c85e5cac2a9 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -248,11 +248,11 @@ struct veth { __be16 h_vlan_TCI; }; -bool tun_is_xdp_buff(void *ptr) +bool tun_is_xdp_frame(void *ptr) { return (unsigned long)ptr & TUN_XDP_FLAG; } -EXPORT_SYMBOL(tun_is_xdp_buff); +EXPORT_SYMBOL(tun_is_xdp_frame); void *tun_xdp_to_ptr(void *ptr) { @@ -660,10 +660,10 @@ void tun_ptr_free(void *ptr) { if (!ptr) return; - if (tun_is_xdp_buff(ptr)) { - struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); - put_page(virt_to_head_page(xdp->data)); + xdp_return_frame(xdpf->data, &xdpf->mem); } else { __skb_array_destroy_skb(ptr); } @@ -1298,17 +1298,14 @@ static const struct net_device_ops tun_netdev_ops = { static int tun_xdp_xmit(struct net_device *dev, struct xdp_buff *xdp) { struct tun_struct *tun = netdev_priv(dev); - struct xdp_buff *buff = xdp->data_hard_start; - int headroom = xdp->data - xdp->data_hard_start; + struct xdp_frame *frame; struct tun_file *tfile; u32 numqueues; int ret = 0; - /* Assure headroom is available and buff is properly aligned */ - if (unlikely(headroom < sizeof(*xdp) || tun_is_xdp_buff(xdp))) - return -ENOSPC; - - *buff = *xdp; + frame = convert_to_xdp_frame(xdp); + if (unlikely(!frame)) + return -EOVERFLOW; rcu_read_lock(); @@ -1323,7 +1320,7 @@ static int tun_xdp_xmit(struct net_device *dev, struct xdp_buff *xdp) /* Encode the XDP flag into lowest bit for consumer to differ * XDP buffer from sk_buff. */ - if (ptr_ring_produce(&tfile->tx_ring, tun_xdp_to_ptr(buff))) { + if (ptr_ring_produce(&tfile->tx_ring, tun_xdp_to_ptr(frame))) { this_cpu_inc(tun->pcpu_stats->tx_dropped); ret = -ENOSPC; } @@ -2001,11 +1998,11 @@ static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) static ssize_t tun_put_user_xdp(struct tun_struct *tun, struct tun_file *tfile, - struct xdp_buff *xdp, + struct xdp_frame *xdp_frame, struct iov_iter *iter) { int vnet_hdr_sz = 0; - size_t size = xdp->data_end - xdp->data; + size_t size = xdp_frame->len; struct tun_pcpu_stats *stats; size_t ret; @@ -2021,7 +2018,7 @@ static ssize_t tun_put_user_xdp(struct tun_struct *tun, iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso)); } - ret = copy_to_iter(xdp->data, size, iter) + vnet_hdr_sz; + ret = copy_to_iter(xdp_frame->data, size, iter) + vnet_hdr_sz; stats = get_cpu_ptr(tun->pcpu_stats); u64_stats_update_begin(&stats->syncp); @@ -2189,11 +2186,11 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, return err; } - if (tun_is_xdp_buff(ptr)) { - struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); - ret = tun_put_user_xdp(tun, tfile, xdp, to); - put_page(virt_to_head_page(xdp->data)); + ret = tun_put_user_xdp(tun, tfile, xdpf, to); + xdp_return_frame(xdpf->data, &xdpf->mem); } else { struct sk_buff *skb = ptr; @@ -2432,10 +2429,10 @@ out_free: static int tun_ptr_peek_len(void *ptr) { if (likely(ptr)) { - if (tun_is_xdp_buff(ptr)) { - struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); - return xdp->data_end - xdp->data; + return xdpf->len; } return __skb_array_len_with_tag(ptr); } else { diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 986058a57917..bbf38befefb2 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -32,6 +32,7 @@ #include #include +#include #include "vhost.h" @@ -181,10 +182,10 @@ static void vhost_net_buf_unproduce(struct vhost_net_virtqueue *nvq) static int vhost_net_buf_peek_len(void *ptr) { - if (tun_is_xdp_buff(ptr)) { - struct xdp_buff *xdp = tun_ptr_to_xdp(ptr); + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); - return xdp->data_end - xdp->data; + return xdpf->len; } return __skb_array_len_with_tag(ptr); -- cgit v1.2.3