From 24ea50127ecf0efe819c1f6230add27abc6ca9d9 Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Wed, 19 Jul 2023 15:24:08 +0200 Subject: xsk: support mbuf on ZC RX Given that skb_shared_info relies on skb_frag_t, in order to support xskb chaining, introduce xdp_buff_xsk::xskb_list_node and xsk_buff_pool::xskb_list. This is needed so ZC drivers can add frags as xskb nodes which will make it possible to handle it both when producing AF_XDP Rx descriptors as well as freeing/recycling all the frags that a single frame carries. Speaking of latter, update xsk_buff_free() to take care of list nodes. For the former (adding as frags), introduce xsk_buff_add_frag() for ZC drivers usage that is going to be used to add a frag to xskb list from pool. xsk_buff_get_frag() will be utilized by XDP_TX and, on contrary, will return xdp_buff. One of the previous patches added a wrapper for ZC Rx so implement xskb list walk and production of Rx descriptors there. On bind() path, bail out if socket wants to use ZC multi-buffer but underlying netdev does not support it. Signed-off-by: Maciej Fijalkowski Link: https://lore.kernel.org/r/20230719132421.584801-12-maciej.fijalkowski@intel.com Signed-off-by: Alexei Starovoitov --- net/xdp/xsk.c | 26 +++++++++++++++++++++++++- net/xdp/xsk_buff_pool.c | 7 +++++++ 2 files changed, 32 insertions(+), 1 deletion(-) (limited to 'net/xdp') diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index ba755fed3750..4f1e0599146e 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -155,8 +155,32 @@ static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff_xsk *xskb, u32 len, static int xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len) { struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp); + u32 frags = xdp_buff_has_frags(xdp); + struct xdp_buff_xsk *pos, *tmp; + struct list_head *xskb_list; + u32 contd = 0; + int err; + + if (frags) + contd = XDP_PKT_CONTD; - return __xsk_rcv_zc(xs, xskb, len, 0); + err = __xsk_rcv_zc(xs, xskb, len, contd); + if (err || likely(!frags)) + goto out; + + xskb_list = &xskb->pool->xskb_list; + list_for_each_entry_safe(pos, tmp, xskb_list, xskb_list_node) { + if (list_is_singular(xskb_list)) + contd = 0; + len = pos->xdp.data_end - pos->xdp.data; + err = __xsk_rcv_zc(xs, pos, len, contd); + if (err) + return err; + list_del(&pos->xskb_list_node); + } + +out: + return err; } static void *xsk_copy_xdp_start(struct xdp_buff *from) diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c index 26f6d304451e..b3f7b310811e 100644 --- a/net/xdp/xsk_buff_pool.c +++ b/net/xdp/xsk_buff_pool.c @@ -86,6 +86,7 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, pool->umem = umem; pool->addrs = umem->addrs; INIT_LIST_HEAD(&pool->free_list); + INIT_LIST_HEAD(&pool->xskb_list); INIT_LIST_HEAD(&pool->xsk_tx_list); spin_lock_init(&pool->xsk_tx_list_lock); spin_lock_init(&pool->cq_lock); @@ -99,6 +100,7 @@ struct xsk_buff_pool *xp_create_and_assign_umem(struct xdp_sock *xs, xskb->pool = pool; xskb->xdp.frame_sz = umem->chunk_size - umem->headroom; INIT_LIST_HEAD(&xskb->free_list_node); + INIT_LIST_HEAD(&xskb->xskb_list_node); if (pool->unaligned) pool->free_heads[i] = xskb; else @@ -187,6 +189,11 @@ int xp_assign_dev(struct xsk_buff_pool *pool, goto err_unreg_pool; } + if (netdev->xdp_zc_max_segs == 1 && (flags & XDP_USE_SG)) { + err = -EOPNOTSUPP; + goto err_unreg_pool; + } + bpf.command = XDP_SETUP_XSK_POOL; bpf.xsk.pool = pool; bpf.xsk.queue_id = queue_id; -- cgit