From: Alexei Starovoitov <ast@xxxxxxxxxx>
Improve selftest to check that btf_load is working from bpf program.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
tools/testing/selftests/bpf/progs/syscall.c | 48 +++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/syscall.c b/tools/testing/selftests/bpf/progs/syscall.c
index 01476f88e45f..b6ac10f75c37 100644
--- a/tools/testing/selftests/bpf/progs/syscall.c
+++ b/tools/testing/selftests/bpf/progs/syscall.c
@@ -4,6 +4,7 @@
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
+#include <linux/btf.h>
#include <../../tools/include/linux/filter.h>
volatile const int workaround = 1;
@@ -18,6 +19,45 @@ struct args {
int prog_fd;
};
+#define BTF_INFO_ENC(kind, kind_flag, vlen) \
+ ((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
+#define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type)
+#define BTF_INT_ENC(encoding, bits_offset, nr_bits) \
+ ((encoding) << 24 | (bits_offset) << 16 | (nr_bits))
+#define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \
+ BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \
+ BTF_INT_ENC(encoding, bits_offset, bits)
+
+static int btf_load(void)
+{
+ struct btf_blob {
+ struct btf_header btf_hdr;
+ __u32 types[8];
+ __u32 str;
+ } raw_btf = {
+ .btf_hdr = {
+ .magic = BTF_MAGIC,
+ .version = BTF_VERSION,
+ .hdr_len = sizeof(struct btf_header),
+ .type_len = sizeof(__u32) * 8,
+ .str_off = sizeof(__u32) * 8,
+ .str_len = sizeof(__u32),
+ },
+ .types = {
+ /* long */
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 64, 8), /* [1] */
+ /* unsigned long */
+ BTF_TYPE_INT_ENC(0, 0, 0, 64, 8), /* [2] */
+ },
+ };
+ static union bpf_attr btf_load_attr = {
+ .btf_size = sizeof(raw_btf),
+ };
+
+ btf_load_attr.btf = (long)&raw_btf;
+ return bpf_sys_bpf(BPF_BTF_LOAD, &btf_load_attr, sizeof(btf_load_attr));
+}
+
SEC("syscall")
int bpf_prog(struct args *ctx)
{
@@ -35,6 +75,8 @@ int bpf_prog(struct args *ctx)
.map_type = BPF_MAP_TYPE_HASH,
.key_size = 8,
.value_size = 8,
+ .btf_key_type_id = 1,
+ .btf_value_type_id = 2,
};
static union bpf_attr map_update_attr = { .map_fd = 1, };
static __u64 key = 12;
@@ -45,7 +87,13 @@ int bpf_prog(struct args *ctx)
};
int ret;
+ ret = btf_load();
+ if (ret < 0)
+ return ret;
+
map_create_attr.max_entries = ctx->max_entries;
+ map_create_attr.btf_fd = ret;
+
prog_load_attr.license = (long) license;
prog_load_attr.insns = (long) insns;
prog_load_attr.log_buf = ctx->log_buf;
--
2.30.2
