samples: bpf: Convert xdp_redirect_kern.o to XDP samples helper

We moved swap_src_dst_mac to xdp_sample.bpf.h to be shared with other
potential users, so drop it while moving code to the new file.
Also, consistently use SEC("xdp") naming instead.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-16-memxor@gmail.com

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 4797784..0b94a6a 100644 (file)
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -163,7 +163,6 @@ always-y += tcp_clamp_kern.o
 always-y += tcp_basertt_kern.o
 always-y += tcp_tos_reflect_kern.o
 always-y += tcp_dumpstats_kern.o
-always-y += xdp_redirect_kern.o
 always-y += xdp_redirect_map_kern.o
 always-y += xdp_redirect_map_multi_kern.o
 always-y += xdp_redirect_cpu_kern.o
@@ -356,6 +355,7 @@ endef
 
 CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
 
+$(obj)/xdp_redirect.bpf.o: $(obj)/xdp_sample.bpf.o
 $(obj)/xdp_monitor.bpf.o: $(obj)/xdp_sample.bpf.o
 
 $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/xdp_sample_shared.h
@@ -366,9 +366,10 @@ $(obj)/%.bpf.o: $(src)/%.bpf.c $(obj)/vmlinux.h $(src)/xdp_sample.bpf.h $(src)/x
                -I$(srctree)/tools/lib $(CLANG_SYS_INCLUDES) \
                -c $(filter %.bpf.c,$^) -o $@
 
-LINKED_SKELS := xdp_monitor.skel.h
+LINKED_SKELS := xdp_redirect.skel.h xdp_monitor.skel.h
 clean-files += $(LINKED_SKELS)
 
+xdp_redirect.skel.h-deps := xdp_redirect.bpf.o xdp_sample.bpf.o
 xdp_monitor.skel.h-deps := xdp_monitor.bpf.o xdp_sample.bpf.o
 
 LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps)))

diff --git a/samples/bpf/xdp_redirect.bpf.c b/samples/bpf/xdp_redirect.bpf.c
new file mode 100644 (file)
index 0000000..7c02bac
--- /dev/null
+++ b/samples/bpf/xdp_redirect.bpf.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include "vmlinux.h"
+#include "xdp_sample.bpf.h"
+#include "xdp_sample_shared.h"
+
+const volatile int ifindex_out;
+
+SEC("xdp")
+int xdp_redirect_prog(struct xdp_md *ctx)
+{
+       void *data_end = (void *)(long)ctx->data_end;
+       void *data = (void *)(long)ctx->data;
+       u32 key = bpf_get_smp_processor_id();
+       struct ethhdr *eth = data;
+       struct datarec *rec;
+       u64 nh_off;
+
+       nh_off = sizeof(*eth);
+       if (data + nh_off > data_end)
+               return XDP_DROP;
+
+       rec = bpf_map_lookup_elem(&rx_cnt, &key);
+       if (!rec)
+               return XDP_PASS;
+       NO_TEAR_INC(rec->processed);
+
+       swap_src_dst_mac(data);
+       return bpf_redirect(ifindex_out, 0);
+}
+
+/* Redirect require an XDP bpf_prog loaded on the TX device */
+SEC("xdp")
+int xdp_redirect_dummy_prog(struct xdp_md *ctx)
+{
+       return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";

diff --git a/samples/bpf/xdp_redirect_kern.c b/samples/bpf/xdp_redirect_kern.c
deleted file mode 100644 (file)
index d26ec3a..0000000
--- a/samples/bpf/xdp_redirect_kern.c
+++ /dev/null
@@ -1,90 +0,0 @@
-/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- */
-#define KBUILD_MODNAME "foo"
-#include <uapi/linux/bpf.h>
-#include <linux/in.h>
-#include <linux/if_ether.h>
-#include <linux/if_packet.h>
-#include <linux/if_vlan.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-#include <bpf/bpf_helpers.h>
-
-struct {
-       __uint(type, BPF_MAP_TYPE_ARRAY);
-       __type(key, int);
-       __type(value, int);
-       __uint(max_entries, 1);
-} tx_port SEC(".maps");
-
-/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
- * feedback.  Redirect TX errors can be caught via a tracepoint.
- */
-struct {
-       __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
-       __type(key, u32);
-       __type(value, long);
-       __uint(max_entries, 1);
-} rxcnt SEC(".maps");
-
-static void swap_src_dst_mac(void *data)
-{
-       unsigned short *p = data;
-       unsigned short dst[3];
-
-       dst[0] = p[0];
-       dst[1] = p[1];
-       dst[2] = p[2];
-       p[0] = p[3];
-       p[1] = p[4];
-       p[2] = p[5];
-       p[3] = dst[0];
-       p[4] = dst[1];
-       p[5] = dst[2];
-}
-
-SEC("xdp_redirect")
-int xdp_redirect_prog(struct xdp_md *ctx)
-{
-       void *data_end = (void *)(long)ctx->data_end;
-       void *data = (void *)(long)ctx->data;
-       struct ethhdr *eth = data;
-       int rc = XDP_DROP;
-       int *ifindex, port = 0;
-       long *value;
-       u32 key = 0;
-       u64 nh_off;
-
-       nh_off = sizeof(*eth);
-       if (data + nh_off > data_end)
-               return rc;
-
-       ifindex = bpf_map_lookup_elem(&tx_port, &port);
-       if (!ifindex)
-               return rc;
-
-       value = bpf_map_lookup_elem(&rxcnt, &key);
-       if (value)
-               *value += 1;
-
-       swap_src_dst_mac(data);
-       return bpf_redirect(*ifindex, 0);
-}
-
-/* Redirect require an XDP bpf_prog loaded on the TX device */
-SEC("xdp_redirect_dummy")
-int xdp_redirect_dummy_prog(struct xdp_md *ctx)
-{
-       return XDP_PASS;
-}
-
-char _license[] SEC("license") = "GPL";