From c6c1f11b691e619802474f886355cb3bc9034021 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bj=C3=B6rn=20T=C3=B6pel?= Date: Wed, 13 Apr 2022 17:30:02 +0200 Subject: [PATCH] xsk: Improve xdp_do_redirect() error codes MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The error codes returned by xdp_do_redirect() when redirecting a frame to an AF_XDP socket has not been very useful. A driver could not distinguish between different errors. Prior this change the following codes where used: Socket not bound or incorrect queue/netdev: EINVAL XDP frame/AF_XDP buffer size mismatch: ENOSPC Could not allocate buffer (copy mode): ENOSPC AF_XDP Rx buffer full: ENOSPC After this change: Socket not bound or incorrect queue/netdev: EINVAL XDP frame/AF_XDP buffer size mismatch: ENOSPC Could not allocate buffer (copy mode): ENOMEM AF_XDP Rx buffer full: ENOBUFS An AF_XDP zero-copy driver can now potentially determine if the failure was due to a full Rx buffer, and if so stop processing more frames, yielding to the userland AF_XDP application. Signed-off-by: Björn Töpel Signed-off-by: Maciej Fijalkowski Signed-off-by: Daniel Borkmann Acked-by: Jesper Dangaard Brouer Link: https://lore.kernel.org/bpf/20220413153015.453864-2-maciej.fijalkowski@intel.com --- net/xdp/xsk.c | 2 +- net/xdp/xsk_queue.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 2c34cae..f75e121 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -184,7 +184,7 @@ static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp) xsk_xdp = xsk_buff_alloc(xs->pool); if (!xsk_xdp) { xs->rx_dropped++; - return -ENOSPC; + return -ENOMEM; } xsk_copy_xdp(xsk_xdp, xdp, len); diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index 801cda5..644479e 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -382,7 +382,7 @@ static inline int xskq_prod_reserve_desc(struct xsk_queue *q, u32 idx; if (xskq_prod_is_full(q)) - return -ENOSPC; + return -ENOBUFS; /* A, matches D */ idx = q->cached_prod++ & q->ring_mask; -- 2.7.4