Merge branch 'libbpf-extend-linker-api-to-support-in-memory-elf-files'

Alastair Robertson says:

====================
libbpf: Extend linker API to support in-memory ELF files

This gives API consumers the option of using anonymous files/memfds to
avoid writing temporary ELFs to disk, which will be useful for performing
linking as part of bpftrace's JIT compilation.

v3:
- Removed "filename" option. Now always generate our own filename for
  passed-in FDs and buffers.
- Use a common function (bpf_linker_add_file) for shared
  implementation of bpf_linker__add_file, bpf_linker__add_fd and
  bpf_linker__add_buf.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Andrii Nakryiko <[email protected]>

Author: anakryiko

tools/lib/bpf/libbpf.h

@@ -1796,9 +1796,14 @@ struct bpf_linker_file_opts {
 struct bpf_linker;
 
 LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
+LIBBPF_API struct bpf_linker *bpf_linker__new_fd(int fd, struct bpf_linker_opts *opts);
 LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
 				    const char *filename,
 				    const struct bpf_linker_file_opts *opts);
+LIBBPF_API int bpf_linker__add_fd(struct bpf_linker *linker, int fd,
+				  const struct bpf_linker_file_opts *opts);
+LIBBPF_API int bpf_linker__add_buf(struct bpf_linker *linker, void *buf, size_t buf_sz,
+				   const struct bpf_linker_file_opts *opts);
 LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
 LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
 

tools/lib/bpf/libbpf.map

@@ -432,4 +432,8 @@ LIBBPF_1.5.0 {
 } LIBBPF_1.4.0;
 
 LIBBPF_1.6.0 {
+	global:
+		bpf_linker__add_buf;
+		bpf_linker__add_fd;
+		bpf_linker__new_fd;
 } LIBBPF_1.5.0;