From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:38146 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751371AbeCIUzf (ORCPT ); Fri, 9 Mar 2018 15:55:35 -0500 Subject: [bpf-next V3 PATCH 06/15] tun: convert to use generic xdp_frame and xdp_return_frame API From: Jesper Dangaard Brouer To: netdev@vger.kernel.org, =?utf-8?b?QmrDtnJu?= =?utf-8?b?VMO2cGVs?= , magnus.karlsson@intel.com Cc: eugenia@mellanox.com, Jason Wang , John Fastabend , Eran Ben Elisha , Saeed Mahameed , galp@mellanox.com, Jesper Dangaard Brouer , Daniel Borkmann , Alexei Starovoitov , Tariq Toukan Date: Fri, 09 Mar 2018 21:55:32 +0100 Message-ID: <152062893221.27458.4551057233989837530.stgit@firesoul> In-Reply-To: <152062887576.27458.8590966896888512270.stgit@firesoul> References: <152062887576.27458.8590966896888512270.stgit@firesoul> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org List-ID: 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 --- drivers/net/tun.c | 43 ++++++++++++++++++++----------------------- drivers/vhost/net.c | 7 ++++--- include/linux/if_tun.h | 4 ++-- 3 files changed, 26 insertions(+), 28 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 475088f947bb..8bb61bd11c6f 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 @@ static 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); } @@ -1290,17 +1290,14 @@ 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(); @@ -1315,7 +1312,7 @@ 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; } @@ -1996,11 +1993,11 @@ 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; @@ -2016,7 +2013,7 @@ 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); @@ -2184,11 +2181,11 @@ 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; @@ -2427,10 +2424,10 @@ static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len, 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 b5fb56b822fd..5aee3aaf6c8c 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -32,6 +32,7 @@ #include #include +#include #include "vhost.h" @@ -177,10 +178,10 @@ 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); diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h index c5b0a75a7812..33b817b172af 100644 --- a/include/linux/if_tun.h +++ b/include/linux/if_tun.h @@ -22,7 +22,7 @@ #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_buff(void *ptr); +bool tun_is_xdp_frame(void *ptr); void *tun_xdp_to_ptr(void *ptr); void *tun_ptr_to_xdp(void *ptr); #else @@ -38,7 +38,7 @@ static inline struct ptr_ring *tun_get_tx_ring(struct file *f) { return ERR_PTR(-EINVAL); } -static inline bool tun_is_xdp_buff(void *ptr) +static inline bool tun_is_xdp_frame(void *ptr) { return false; }