Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2024-06-06

We've added 54 non-merge commits during the last 10 day(s) which contain
a total of 50 files changed, 1887 insertions(+), 527 deletions(-).

The main changes are:

1) Add a user space notification mechanism via epoll when a struct_ops
   object is getting detached/unregistered, from Kui-Feng Lee.

2) Big batch of BPF selftest refactoring for sockmap and BPF congctl
   tests, from Geliang Tang.

3) Add BTF field (type and string fields, right now) iterator support
   to libbpf instead of using existing callback-based approaches,
   from Andrii Nakryiko.

4) Extend BPF selftests for the latter with a new btf_field_iter
   selftest, from Alan Maguire.

5) Add new kfuncs for a generic, open-coded bits iterator,
   from Yafang Shao.

6) Fix BPF selftests' kallsyms_find() helper under kernels configured
   with CONFIG_LTO_CLANG_THIN, from Yonghong Song.

7) Remove a bunch of unused structs in BPF selftests,
   from David Alan Gilbert.

8) Convert test_sockmap section names into names understood by libbpf
   so it can deduce program type and attach type, from Jakub Sitnicki.

9) Extend libbpf with the ability to configure log verbosity
   via LIBBPF_LOG_LEVEL environment variable, from Mykyta Yatsenko.

10) Fix BPF selftests with regards to bpf_cookie and find_vma flakiness
    in nested VMs, from Song Liu.

11) Extend riscv32/64 JITs to introduce shift/add helpers to generate Zba
    optimization, from Xiao Wang.

12) Enable BPF programs to declare arrays and struct fields with kptr,
    bpf_rb_root, and bpf_list_head, from Kui-Feng Lee.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits)
  selftests/bpf: Drop useless arguments of do_test in bpf_tcp_ca
  selftests/bpf: Use start_test in test_dctcp in bpf_tcp_ca
  selftests/bpf: Use start_test in test_dctcp_fallback in bpf_tcp_ca
  selftests/bpf: Add start_test helper in bpf_tcp_ca
  selftests/bpf: Use connect_to_fd_opts in do_test in bpf_tcp_ca
  libbpf: Auto-attach struct_ops BPF maps in BPF skeleton
  selftests/bpf: Add btf_field_iter selftests
  selftests/bpf: Fix send_signal test with nested CONFIG_PARAVIRT
  libbpf: Remove callback-based type/string BTF field visitor helpers
  bpftool: Use BTF field iterator in btfgen
  libbpf: Make use of BTF field iterator in BTF handling code
  libbpf: Make use of BTF field iterator in BPF linker code
  libbpf: Add BTF field iterator
  selftests/bpf: Ignore .llvm.<hash> suffix in kallsyms_find()
  selftests/bpf: Fix bpf_cookie and find_vma in nested VM
  selftests/bpf: Test global bpf_list_head arrays.
  selftests/bpf: Test global bpf_rb_root arrays and fields in nested struct types.
  selftests/bpf: Test kptr arrays and kptrs in nested struct fields.
  bpf: limit the number of levels of a nested struct type.
  bpf: look into the types of the fields of a struct type recursively.
  ...
====================

Link: https://lore.kernel.org/r/20240606223146.23020-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 27 insertions, 9 deletions

diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index a0dcfb82e455..e2f06609c624 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -508,11 +508,33 @@ struct bpf_line_info_min {
 	__u32	line_col;
 };
 
+enum btf_field_iter_kind {
+	BTF_FIELD_ITER_IDS,
+	BTF_FIELD_ITER_STRS,
+};
+
+struct btf_field_desc {
+	/* once-per-type offsets */
+	int t_off_cnt, t_offs[2];
+	/* member struct size, or zero, if no members */
+	int m_sz;
+	/* repeated per-member offsets */
+	int m_off_cnt, m_offs[1];
+};
+
+struct btf_field_iter {
+	struct btf_field_desc desc;
+	void *p;
+	int m_idx;
+	int off_idx;
+	int vlen;
+};
+
+int btf_field_iter_init(struct btf_field_iter *it, struct btf_type *t, enum btf_field_iter_kind iter_kind);
+__u32 *btf_field_iter_next(struct btf_field_iter *it);
 
 typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx);
 typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx);
-int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx);
-int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx);
 int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx);
 int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx);
 __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name,
@@ -597,13 +619,9 @@ static inline int ensure_good_fd(int fd)
 	return fd;
 }
 
-static inline int sys_dup2(int oldfd, int newfd)
+static inline int sys_dup3(int oldfd, int newfd, int flags)
 {
-#ifdef __NR_dup2
-	return syscall(__NR_dup2, oldfd, newfd);
-#else
-	return syscall(__NR_dup3, oldfd, newfd, 0);
-#endif
+	return syscall(__NR_dup3, oldfd, newfd, flags);
 }
 
 /* Point *fixed_fd* to the same file that *tmp_fd* points to.
@@ -614,7 +632,7 @@ static inline int reuse_fd(int fixed_fd, int tmp_fd)
 {
 	int err;
 
-	err = sys_dup2(tmp_fd, fixed_fd);
+	err = sys_dup3(tmp_fd, fixed_fd, O_CLOEXEC);
 	err = err < 0 ? -errno : 0;
 	close(tmp_fd); /* clean up temporary FD */
 	return err;