From bbaf6029c49ccf2dc93d9564af58a20d125947a1 Mon Sep 17 00:00:00 2001 From: Maciej Fijalkowski Date: Fri, 1 Feb 2019 22:42:25 +0100 Subject: samples/bpf: Convert XDP samples to libbpf usage Some of XDP samples that are attaching the bpf program to the interface via libbpf's bpf_set_link_xdp_fd are still using the bpf_load.c for loading and manipulating the ebpf program and maps. Convert them to do this through libbpf usage and remove bpf_load from the picture. While at it remove what looks like debug leftover in xdp_redirect_map_user.c In xdp_redirect_cpu, change the way that the program to be loaded onto interface is chosen - user now needs to pass the program's section name instead of the relative number. In case of typo print out the section names to choose from. Signed-off-by: Maciej Fijalkowski Reviewed-by: Jakub Kicinski Acked-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann --- samples/bpf/xdp_redirect_user.c | 44 +++++++++++++++++++++++++++++++---------- 1 file changed, 34 insertions(+), 10 deletions(-) (limited to 'samples/bpf/xdp_redirect_user.c') diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c index 81a69e36cb78..93404820df68 100644 --- a/samples/bpf/xdp_redirect_user.c +++ b/samples/bpf/xdp_redirect_user.c @@ -22,15 +22,16 @@ #include #include -#include "bpf_load.h" #include "bpf_util.h" #include +#include "bpf/libbpf.h" static int ifindex_in; static int ifindex_out; static bool ifindex_out_xdp_dummy_attached = true; static __u32 xdp_flags; +static int rxcnt_map_fd; static void int_exit(int sig) { @@ -53,7 +54,7 @@ static void poll_stats(int interval, int ifindex) int i; sleep(interval); - assert(bpf_map_lookup_elem(map_fd[1], &key, values) == 0); + assert(bpf_map_lookup_elem(rxcnt_map_fd, &key, values) == 0); for (i = 0; i < nr_cpus; i++) sum += (values[i] - prev[i]); if (sum) @@ -77,9 +78,16 @@ static void usage(const char *prog) int main(int argc, char **argv) { struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; + struct bpf_prog_load_attr prog_load_attr = { + .prog_type = BPF_PROG_TYPE_XDP, + }; + struct bpf_program *prog, *dummy_prog; + int prog_fd, tx_port_map_fd, opt; const char *optstr = "SN"; + struct bpf_object *obj; char filename[256]; - int ret, opt, key = 0; + int dummy_prog_fd; + int ret, key = 0; while ((opt = getopt(argc, argv, optstr)) != -1) { switch (opt) { @@ -110,24 +118,40 @@ int main(int argc, char **argv) printf("input: %d output: %d\n", ifindex_in, ifindex_out); snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + prog_load_attr.file = filename; - if (load_bpf_file(filename)) { - printf("%s", bpf_log_buf); + if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd)) + return 1; + + prog = bpf_program__next(NULL, obj); + dummy_prog = bpf_program__next(prog, obj); + if (!prog || !dummy_prog) { + printf("finding a prog in obj file failed\n"); + return 1; + } + /* bpf_prog_load_xattr gives us the pointer to first prog's fd, + * so we're missing only the fd for dummy prog + */ + dummy_prog_fd = bpf_program__fd(dummy_prog); + if (prog_fd < 0 || dummy_prog_fd < 0) { + printf("bpf_prog_load_xattr: %s\n", strerror(errno)); return 1; } - if (!prog_fd[0]) { - printf("load_bpf_file: %s\n", strerror(errno)); + tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port"); + rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt"); + if (tx_port_map_fd < 0 || rxcnt_map_fd < 0) { + printf("bpf_object__find_map_fd_by_name failed\n"); return 1; } - if (bpf_set_link_xdp_fd(ifindex_in, prog_fd[0], xdp_flags) < 0) { + if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) { printf("ERROR: link set xdp fd failed on %d\n", ifindex_in); return 1; } /* Loading dummy XDP prog on out-device */ - if (bpf_set_link_xdp_fd(ifindex_out, prog_fd[1], + if (bpf_set_link_xdp_fd(ifindex_out, dummy_prog_fd, (xdp_flags | XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) { printf("WARN: link set xdp fd failed on %d\n", ifindex_out); ifindex_out_xdp_dummy_attached = false; @@ -137,7 +161,7 @@ int main(int argc, char **argv) signal(SIGTERM, int_exit); /* bpf redirect port */ - ret = bpf_map_update_elem(map_fd[0], &key, &ifindex_out, 0); + ret = bpf_map_update_elem(tx_port_map_fd, &key, &ifindex_out, 0); if (ret) { perror("bpf_update_elem"); goto out; -- cgit v1.2.3-59-g8ed1b