openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

bpf: finally expose xdp_rxq_info to XDP bpf-programs 

Now all XDP driver have been updated to setup xdp_rxq_info and assign
this to xdp_buff->rxq.  Thus, it is now safe to enable access to some
of the xdp_rxq_info struct members.

This patch extend xdp_md and expose UAPI to userspace for
ingress_ifindex and rx_queue_index.  Access happens via bpf
instruction rewrite, that load data directly from struct xdp_rxq_info.

* ingress_ifindex map to xdp_rxq_info->dev->ifindex
* rx_queue_index  map to xdp_rxq_info->queue_index

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Jesper Dangaard Brouer 2018-01-03 11:26:14 +01:00 committed by Alexei Starovoitov
parent e817f85652
commit 02dd3291b2
2 changed files with 22 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
include/uapi/linux/bpf.h
View File

@ -899,6 +899,9 @@ struct xdp_md {
__u32 data;
__u32 data_end;
__u32 data_meta;
/* Below access go though struct xdp_rxq_info */
__u32 ingress_ifindex; /* rxq->dev->ifindex */
__u32 rx_queue_index; /* rxq->queue_index */
};
enum sk_action {

19
net/core/filter.c
View File

@ -4304,6 +4304,25 @@ static u32 xdp_convert_ctx_access(enum bpf_access_type type,
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, data_end));
break;
case offsetof(struct xdp_md, ingress_ifindex):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, rxq));
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
si->dst_reg, si->dst_reg,
offsetof(struct xdp_rxq_info, dev));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct net_device,
ifindex, 4, target_size));
break;
case offsetof(struct xdp_md, rx_queue_index):
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
si->dst_reg, si->src_reg,
offsetof(struct xdp_buff, rxq));
*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
bpf_target_off(struct xdp_rxq_info,
queue_index, 4, target_size));
break;
}
return insn - insn_buf;