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Creating a bpf sample that shows howto use the XDP 'data_meta' infrastructure, created by Daniel Borkmann. Very few drivers support this feature, but I wanted a functional sample to begin with, when working on adding driver support. XDP data_meta is about creating a communication channel between BPF programs. This can be XDP tail-progs, but also other SKB based BPF hooks, like in this case the TC clsact hook. In this sample I show that XDP can store info named "mark", and TC/clsact chooses to use this info and store it into the skb->mark. It is a bit annoying that XDP and TC samples uses different tools/libs when attaching their BPF hooks. As the XDP and TC programs need to cooperate and agree on a struct-layout, it is best/easiest if the two programs can be contained within the same BPF restricted-C file. As the bpf-loader, I choose to not use bpf_load.c (or libbpf), but instead wrote a bash shell scripted named xdp2skb_meta.sh, which demonstrate howto use the iproute cmdline tools 'tc' and 'ip' for loading BPF programs. To make it easy for first time users, the shell script have command line parsing, and support --verbose and --dry-run mode, if you just want to see/learn the tc+ip command syntax: # ./xdp2skb_meta.sh --dev ixgbe2 --dry-run # Dry-run mode: enable VERBOSE and don't call TC+IP tc qdisc del dev ixgbe2 clsact tc qdisc add dev ixgbe2 clsact tc filter add dev ixgbe2 ingress prio 1 handle 1 bpf da obj ./xdp2skb_meta_kern.o sec tc_mark # Flush XDP on device: ixgbe2 ip link set dev ixgbe2 xdp off ip link set dev ixgbe2 xdp obj ./xdp2skb_meta_kern.o sec xdp_mark Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
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| .. | ||
| auxdisplay | ||
| blackfin | ||
| bpf | ||
| configfs | ||
| connector | ||
| hidraw | ||
| hw_breakpoint | ||
| kdb | ||
| kfifo | ||
| kobject | ||
| kprobes | ||
| livepatch | ||
| mei | ||
| mic/mpssd | ||
| pktgen | ||
| rpmsg | ||
| seccomp | ||
| sockmap | ||
| statx | ||
| timers | ||
| trace_events | ||
| trace_printk | ||
| uhid | ||
| v4l | ||
| vfio-mdev | ||
| watchdog | ||
| Kconfig | ||
| Makefile | ||