From 173d3adb6f437037f216270955886ca9878187a5 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Mon, 4 Jun 2018 14:05:55 +0200 Subject: xsk: add zero-copy support for Rx MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Extend the xsk_rcv to support the new MEM_TYPE_ZERO_COPY memory, and wireup ndo_bpf call in bind. Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann --- net/xdp/xdp_umem.c | 77 +++++++++++++++++++++++++++++++++++++++++++ net/xdp/xdp_umem.h | 3 ++ net/xdp/xsk.c | 96 ++++++++++++++++++++++++++++++++++++++++++------------ 3 files changed, 156 insertions(+), 20 deletions(-) (limited to 'net') diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index aca826011f6c..f729d79b8d91 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -17,6 +17,81 @@ #define XDP_UMEM_MIN_CHUNK_SIZE 2048 +int xdp_umem_assign_dev(struct xdp_umem *umem, struct net_device *dev, + u32 queue_id, u16 flags) +{ + bool force_zc, force_copy; + struct netdev_bpf bpf; + int err; + + force_zc = flags & XDP_ZEROCOPY; + force_copy = flags & XDP_COPY; + + if (force_zc && force_copy) + return -EINVAL; + + if (force_copy) + return 0; + + dev_hold(dev); + + if (dev->netdev_ops->ndo_bpf) { + bpf.command = XDP_QUERY_XSK_UMEM; + + rtnl_lock(); + err = dev->netdev_ops->ndo_bpf(dev, &bpf); + rtnl_unlock(); + + if (err) { + dev_put(dev); + return force_zc ? -ENOTSUPP : 0; + } + + bpf.command = XDP_SETUP_XSK_UMEM; + bpf.xsk.umem = umem; + bpf.xsk.queue_id = queue_id; + + rtnl_lock(); + err = dev->netdev_ops->ndo_bpf(dev, &bpf); + rtnl_unlock(); + + if (err) { + dev_put(dev); + return force_zc ? err : 0; /* fail or fallback */ + } + + umem->dev = dev; + umem->queue_id = queue_id; + umem->zc = true; + return 0; + } + + dev_put(dev); + return force_zc ? -ENOTSUPP : 0; /* fail or fallback */ +} + +void xdp_umem_clear_dev(struct xdp_umem *umem) +{ + struct netdev_bpf bpf; + int err; + + if (umem->dev) { + bpf.command = XDP_SETUP_XSK_UMEM; + bpf.xsk.umem = NULL; + bpf.xsk.queue_id = umem->queue_id; + + rtnl_lock(); + err = umem->dev->netdev_ops->ndo_bpf(umem->dev, &bpf); + rtnl_unlock(); + + if (err) + WARN(1, "failed to disable umem!\n"); + + dev_put(umem->dev); + umem->dev = NULL; + } +} + static void xdp_umem_unpin_pages(struct xdp_umem *umem) { unsigned int i; @@ -43,6 +118,8 @@ static void xdp_umem_release(struct xdp_umem *umem) struct task_struct *task; struct mm_struct *mm; + xdp_umem_clear_dev(umem); + if (umem->fq) { xskq_destroy(umem->fq); umem->fq = NULL; diff --git a/net/xdp/xdp_umem.h b/net/xdp/xdp_umem.h index 40e8fa4a92af..674508a32a4d 100644 --- a/net/xdp/xdp_umem.h +++ b/net/xdp/xdp_umem.h @@ -13,6 +13,9 @@ static inline char *xdp_umem_get_data(struct xdp_umem *umem, u64 addr) return umem->pages[addr >> PAGE_SHIFT].addr + (addr & (PAGE_SIZE - 1)); } +int xdp_umem_assign_dev(struct xdp_umem *umem, struct net_device *dev, + u32 queue_id, u16 flags); +void xdp_umem_clear_dev(struct xdp_umem *umem); bool xdp_umem_validate_queues(struct xdp_umem *umem); void xdp_get_umem(struct xdp_umem *umem); void xdp_put_umem(struct xdp_umem *umem); diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 4688c750df1d..ab64bd8260ea 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -36,19 +36,28 @@ static struct xdp_sock *xdp_sk(struct sock *sk) bool xsk_is_setup_for_bpf_map(struct xdp_sock *xs) { - return !!xs->rx; + return READ_ONCE(xs->rx) && READ_ONCE(xs->umem) && + READ_ONCE(xs->umem->fq); } -static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) +u64 *xsk_umem_peek_addr(struct xdp_umem *umem, u64 *addr) +{ + return xskq_peek_addr(umem->fq, addr); +} +EXPORT_SYMBOL(xsk_umem_peek_addr); + +void xsk_umem_discard_addr(struct xdp_umem *umem) +{ + xskq_discard_addr(umem->fq); +} +EXPORT_SYMBOL(xsk_umem_discard_addr); + +static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) { - u32 len = xdp->data_end - xdp->data; void *buffer; u64 addr; int err; - if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) - return -EINVAL; - if (!xskq_peek_addr(xs->umem->fq, &addr) || len > xs->umem->chunk_size_nohr) { xs->rx_dropped++; @@ -60,25 +69,41 @@ static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) buffer = xdp_umem_get_data(xs->umem, addr); memcpy(buffer, xdp->data, len); err = xskq_produce_batch_desc(xs->rx, addr, len); - if (!err) + if (!err) { xskq_discard_addr(xs->umem->fq); - else - xs->rx_dropped++; + xdp_return_buff(xdp); + return 0; + } + xs->rx_dropped++; return err; } -int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) +static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) { - int err; + int err = xskq_produce_batch_desc(xs->rx, (u64)xdp->handle, len); - err = __xsk_rcv(xs, xdp); - if (likely(!err)) + if (err) { xdp_return_buff(xdp); + xs->rx_dropped++; + } return err; } +int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) +{ + u32 len; + + if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) + return -EINVAL; + + len = xdp->data_end - xdp->data; + + return (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) ? + __xsk_rcv_zc(xs, xdp, len) : __xsk_rcv(xs, xdp, len); +} + void xsk_flush(struct xdp_sock *xs) { xskq_produce_flush_desc(xs->rx); @@ -87,12 +112,29 @@ void xsk_flush(struct xdp_sock *xs) int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) { + u32 len = xdp->data_end - xdp->data; + void *buffer; + u64 addr; int err; - err = __xsk_rcv(xs, xdp); - if (!err) + if (!xskq_peek_addr(xs->umem->fq, &addr) || + len > xs->umem->chunk_size_nohr) { + xs->rx_dropped++; + return -ENOSPC; + } + + addr += xs->umem->headroom; + + buffer = xdp_umem_get_data(xs->umem, addr); + memcpy(buffer, xdp->data, len); + err = xskq_produce_batch_desc(xs->rx, addr, len); + if (!err) { + xskq_discard_addr(xs->umem->fq); xsk_flush(xs); + return 0; + } + xs->rx_dropped++; return err; } @@ -291,6 +333,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) struct sock *sk = sock->sk; struct xdp_sock *xs = xdp_sk(sk); struct net_device *dev; + u32 flags, qid; int err = 0; if (addr_len < sizeof(struct sockaddr_xdp)) @@ -315,16 +358,26 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) goto out_unlock; } - if ((xs->rx && sxdp->sxdp_queue_id >= dev->real_num_rx_queues) || - (xs->tx && sxdp->sxdp_queue_id >= dev->real_num_tx_queues)) { + qid = sxdp->sxdp_queue_id; + + if ((xs->rx && qid >= dev->real_num_rx_queues) || + (xs->tx && qid >= dev->real_num_tx_queues)) { err = -EINVAL; goto out_unlock; } - if (sxdp->sxdp_flags & XDP_SHARED_UMEM) { + flags = sxdp->sxdp_flags; + + if (flags & XDP_SHARED_UMEM) { struct xdp_sock *umem_xs; struct socket *sock; + if ((flags & XDP_COPY) || (flags & XDP_ZEROCOPY)) { + /* Cannot specify flags for shared sockets. */ + err = -EINVAL; + goto out_unlock; + } + if (xs->umem) { /* We have already our own. */ err = -EINVAL; @@ -343,8 +396,7 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) err = -EBADF; sockfd_put(sock); goto out_unlock; - } else if (umem_xs->dev != dev || - umem_xs->queue_id != sxdp->sxdp_queue_id) { + } else if (umem_xs->dev != dev || umem_xs->queue_id != qid) { err = -EINVAL; sockfd_put(sock); goto out_unlock; @@ -360,6 +412,10 @@ static int xsk_bind(struct socket *sock, struct sockaddr *addr, int addr_len) /* This xsk has its own umem. */ xskq_set_umem(xs->umem->fq, &xs->umem->props); xskq_set_umem(xs->umem->cq, &xs->umem->props); + + err = xdp_umem_assign_dev(xs->umem, dev, qid, flags); + if (err) + goto out_unlock; } xs->dev = dev; -- cgit