[PATCH bpf-next v4 5/7] xdp: add xdp_do_redirect_frame() for pre-computed xdp_frames
From: Toke Høiland-Jørgensen <hidden>
Date: 2021-12-17 00:28:10
Also in:
bpf
Subsystem:
bpf [core], bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Add an xdp_do_redirect_frame() variant which supports pre-computed xdp_frame structures. This will be used in bpf_prog_run() to avoid having to write to the xdp_frame structure when the XDP program doesn't modify the frame boundaries. Signed-off-by: Toke Høiland-Jørgensen <redacted> --- include/linux/filter.h | 4 +++ net/core/filter.c | 65 +++++++++++++++++++++++++++++++++++------- 2 files changed, 58 insertions(+), 11 deletions(-)
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 60eec80fa1d4..71fa57b88bfc 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h@@ -1019,6 +1019,10 @@ int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb, int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *prog); +int xdp_do_redirect_frame(struct net_device *dev, + struct xdp_buff *xdp, + struct xdp_frame *xdpf, + struct bpf_prog *prog); void xdp_do_flush(void); /* The xdp_do_flush_map() helper has been renamed to drop the _map suffix, as
diff --git a/net/core/filter.c b/net/core/filter.c
index f4540c800f4a..663a5d5370d5 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c@@ -3957,26 +3957,44 @@ u32 xdp_master_redirect(struct xdp_buff *xdp) } EXPORT_SYMBOL_GPL(xdp_master_redirect); -int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, - struct bpf_prog *xdp_prog) +static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri, + struct net_device *dev, + struct xdp_buff *xdp, + struct bpf_prog *xdp_prog) { - struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); enum bpf_map_type map_type = ri->map_type; void *fwd = ri->tgt_value; u32 map_id = ri->map_id; - struct xdp_frame *xdpf; - struct bpf_map *map; int err; ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */ ri->map_type = BPF_MAP_TYPE_UNSPEC; - if (map_type == BPF_MAP_TYPE_XSKMAP) { - err = __xsk_map_redirect(fwd, xdp); - goto out; - } + err = __xsk_map_redirect(fwd, xdp); + if (unlikely(err)) + goto err; + + _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index); + return 0; +err: + _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err); + return err; +} + +static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri, + struct net_device *dev, + struct xdp_frame *xdpf, + struct bpf_prog *xdp_prog) +{ + enum bpf_map_type map_type = ri->map_type; + void *fwd = ri->tgt_value; + u32 map_id = ri->map_id; + struct bpf_map *map; + int err; + + ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */ + ri->map_type = BPF_MAP_TYPE_UNSPEC; - xdpf = xdp_convert_buff_to_frame(xdp); if (unlikely(!xdpf)) { err = -EOVERFLOW; goto err;
@@ -4013,7 +4031,6 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, err = -EBADRQC; } -out: if (unlikely(err)) goto err;
@@ -4023,8 +4040,34 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err); return err; } + +int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, + struct bpf_prog *xdp_prog) +{ + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + enum bpf_map_type map_type = ri->map_type; + + if (map_type == BPF_MAP_TYPE_XSKMAP) + return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog); + + return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp), + xdp_prog); +} EXPORT_SYMBOL_GPL(xdp_do_redirect); +int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp, + struct xdp_frame *xdpf, struct bpf_prog *xdp_prog) +{ + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + enum bpf_map_type map_type = ri->map_type; + + if (map_type == BPF_MAP_TYPE_XSKMAP) + return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog); + + return __xdp_do_redirect_frame(ri, dev, xdpf, xdp_prog); +} +EXPORT_SYMBOL_GPL(xdp_do_redirect_frame); + static int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb, struct xdp_buff *xdp,
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2.34.1