[PATCH bpf-next v8 15/22] libbpf: Add cleanup_info to bpf_prog_load_opts

[Yonghong Song <yonghong.song@linux.dev>]

Let a caller hand the kernel an exception cleanup table: struct
bpf_prog_load_opts grows cleanup_info_cnt, cleanup_info and
cleanup_info_rec_size, and bpf_prog_load() passes all three on to
BPF_PROG_LOAD.

The attr size it computes now ends at cleanup_info_cnt, the last of the
three new fields in the BPF_PROG_LOAD attr, so it covers all of them. In
the opts, cleanup_info_cnt comes first so that it fills the four bytes
after fd_array_cnt the pointer would otherwise leave as a hole.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 tools/lib/bpf/bpf.c | 6 +++++-
 tools/lib/bpf/bpf.h | 7 ++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index b49822d212ae..b4031f62bdee 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -295,7 +295,7 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 		  const struct bpf_insn *insns, size_t insn_cnt,
 		  struct bpf_prog_load_opts *opts)
 {
-	const size_t attr_sz = offsetofend(union bpf_attr, keyring_id);
+	const size_t attr_sz = offsetofend(union bpf_attr, cleanup_info_cnt);
 	void *finfo = NULL, *linfo = NULL;
 	const char *func_info, *line_info;
 	__u32 log_size, log_level, attach_prog_fd, attach_btf_obj_fd;
@@ -370,6 +370,10 @@ int bpf_prog_load(enum bpf_prog_type prog_type,
 	attr.fd_array = ptr_to_u64(OPTS_GET(opts, fd_array, NULL));
 	attr.fd_array_cnt = OPTS_GET(opts, fd_array_cnt, 0);
 
+	attr.cleanup_info = ptr_to_u64(OPTS_GET(opts, cleanup_info, NULL));
+	attr.cleanup_info_rec_size = OPTS_GET(opts, cleanup_info_rec_size, 0);
+	attr.cleanup_info_cnt = OPTS_GET(opts, cleanup_info_cnt, 0);
+
 	if (log_level) {
 		attr.log_buf = ptr_to_u64(log_buf);
 		attr.log_size = log_size;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 826d9cc9ab65..cbe56ddc8cf7 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -128,9 +128,14 @@ struct bpf_prog_load_opts {
 
 	/* if set, provides the length of fd_array */
 	__u32 fd_array_cnt;
+
+	/* exception cleanup table, from the .bpf_cleanup section */
+	__u32 cleanup_info_cnt;
+	const void *cleanup_info;
+	__u32 cleanup_info_rec_size;
 	size_t :0;
 };
-#define bpf_prog_load_opts__last_field fd_array_cnt
+#define bpf_prog_load_opts__last_field cleanup_info_rec_size
 
 LIBBPF_API int bpf_prog_load(enum bpf_prog_type prog_type,
 			     const char *prog_name, const char *license,
-- 
2.53.0-Meta