@@ -389,7 +389,7 @@ void btf__free(struct btf *btf)
if (!btf)
return;
- if (btf->fd != -1)
+ if (btf->fd >= 0)
close(btf->fd);
free(btf->data);
@@ -700,6 +700,11 @@ int btf__fd(const struct btf *btf)
return btf->fd;
}
+void btf__set_fd(struct btf *btf, int fd)
+{
+ btf->fd = fd;
+}
+
const void *btf__get_raw_data(const struct btf *btf, __u32 *size)
{
*size = btf->data_size;
@@ -79,6 +79,7 @@ LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__align_of(const struct btf *btf, __u32 id);
LIBBPF_API int btf__fd(const struct btf *btf);
+LIBBPF_API void btf__set_fd(struct btf *btf, int fd);
LIBBPF_API const void *btf__get_raw_data(const struct btf *btf, __u32 *size);
LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
LIBBPF_API int btf__get_from_id(__u32 id, struct btf **btf);
@@ -288,4 +288,5 @@ LIBBPF_0.1.0 {
bpf_map__value_size;
bpf_program__autoload;
bpf_program__set_autoload;
+ btf__set_fd;
} LIBBPF_0.0.9;
Add setter for BTF FD to allow application more fine-grained control in more advanced scenarios. Storing BTF FD inside `struct btf` provides little benefit and probably would be better done differently (e.g., btf__load() could just return FD on success), but we are stuck with this due to backwards compatibility. The main problem is that it's impossible to load BTF and than free user-space memory, but keep FD intact, because `struct btf` assumes ownership of that FD upon successful load and will attempt to close it during btf__free(). To allow callers (e.g., libbpf itself for BTF sanitization) to have more control over this, add btf__set_fd() to allow to reset FD arbitrarily, if necessary. Signed-off-by: Andrii Nakryiko <andriin@fb.com> --- tools/lib/bpf/btf.c | 7 ++++++- tools/lib/bpf/btf.h | 1 + tools/lib/bpf/libbpf.map | 1 + 3 files changed, 8 insertions(+), 1 deletion(-)