Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-09-23

The following pull-request contains BPF updates for your *net-next* tree.

We've added 95 non-merge commits during the last 22 day(s) which contain
a total of 124 files changed, 4211 insertions(+), 2040 deletions(-).

The main changes are:

1) Full multi function support in libbpf, from Andrii.

2) Refactoring of function argument checks, from Lorenz.

3) Make bpf_tail_call compatible with functions (subprograms), from Maciej.

4) Program metadata support, from YiFei.

5) bpf iterator optimizations, from Yonghong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 61 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c
new file mode 100644
index 000000000000..96dbef2b6b7c
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf3.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_legacy.h"
+
+struct {
+	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+	__uint(max_entries, 2);
+	__uint(key_size, sizeof(__u32));
+	__uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+__noinline
+int subprog_tail2(struct __sk_buff *skb)
+{
+	volatile char arr[64] = {};
+
+	if (load_word(skb, 0) || load_half(skb, 0))
+		bpf_tail_call(skb, &jmp_table, 10);
+	else
+		bpf_tail_call(skb, &jmp_table, 1);
+
+	return skb->len;
+}
+
+static __noinline
+int subprog_tail(struct __sk_buff *skb)
+{
+	volatile char arr[64] = {};
+
+	bpf_tail_call(skb, &jmp_table, 0);
+
+	return skb->len * 2;
+}
+
+SEC("classifier/0")
+int bpf_func_0(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	return subprog_tail2(skb);
+}
+
+SEC("classifier/1")
+int bpf_func_1(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	return skb->len * 3;
+}
+
+SEC("classifier")
+int entry(struct __sk_buff *skb)
+{
+	volatile char arr[128] = {};
+
+	return subprog_tail(skb);
+}
+
+char __license[] SEC("license") = "GPL";
+int _version SEC("version") = 1;