@@ -854,6 +854,13 @@ int bpf_link_create(int prog_fd, int target_fd,
if (!OPTS_ZEROED(opts, perf_event))
return libbpf_err(-EINVAL);
break;
+ case BPF_TRACE_FENTRY:
+ case BPF_TRACE_FEXIT:
+ case BPF_MODIFY_RETURN:
+ attr.link_create.tracing.bpf_cookie = OPTS_GET(opts, tracing.bpf_cookie, 0);
+ if (!OPTS_ZEROED(opts, tracing))
+ return libbpf_err(-EINVAL);
+ break;
default:
if (!OPTS_ZEROED(opts, flags))
return libbpf_err(-EINVAL);
@@ -410,6 +410,9 @@ struct bpf_link_create_opts {
__u32 iter_info_len;
__u32 target_btf_id;
union {
+ struct {
+ __u64 bpf_cookie;
+ } tracing;
struct {
__u64 bpf_cookie;
} perf_event;
@@ -10611,6 +10611,39 @@ struct bpf_link *bpf_program__attach_trace(const struct bpf_program *prog)
return bpf_program__attach_btf_id(prog);
}
+struct bpf_link *bpf_program__attach_trace_opts(const struct bpf_program *prog,
+ const struct bpf_trace_opts *opts)
+{
+ char errmsg[STRERR_BUFSIZE];
+ struct bpf_link *link;
+ int prog_fd, pfd;
+
+ LIBBPF_OPTS(bpf_link_create_opts, link_opts);
+
+ prog_fd = bpf_program__fd(prog);
+ if (prog_fd < 0) {
+ pr_warn("prog '%s': can't attach before loaded\n", prog->name);
+ return libbpf_err_ptr(-EINVAL);
+ }
+
+ link = calloc(1, sizeof(*link));
+ if (!link)
+ return libbpf_err_ptr(-ENOMEM);
+ link->detach = &bpf_link__detach_fd;
+
+ link_opts.tracing.bpf_cookie = OPTS_GET(opts, bpf_cookie, 0);
+ pfd = bpf_link_create(prog_fd, 0, prog->expected_attach_type, &link_opts);
+ if (pfd < 0) {
+ pfd = -errno;
+ free(link);
+ pr_warn("prog '%s': failed to attach: %s\n",
+ prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg)));
+ return libbpf_err_ptr(pfd);
+ }
+ link->fd = pfd;
+ return (struct bpf_link *)link;
+}
+
struct bpf_link *bpf_program__attach_lsm(const struct bpf_program *prog)
{
return bpf_program__attach_btf_id(prog);
@@ -501,8 +501,20 @@ bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
LIBBPF_API struct bpf_link *
bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
const char *tp_name);
+
+struct bpf_trace_opts {
+ /* size of this struct, for forward/backward compatibility */
+ size_t sz;
+ /* custom user-provided value fetchable through bpf_get_attach_cookie() */
+ __u64 bpf_cookie;
+};
+#define bpf_trace_opts__last_field bpf_cookie
+
LIBBPF_API struct bpf_link *
bpf_program__attach_trace(const struct bpf_program *prog);
+LIBBPF_API struct bpf_link *
+bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts);
+
LIBBPF_API struct bpf_link *
bpf_program__attach_lsm(const struct bpf_program *prog);
LIBBPF_API struct bpf_link *
@@ -424,6 +424,7 @@ LIBBPF_0.6.0 {
LIBBPF_0.7.0 {
global:
bpf_btf_load;
+ bpf_program__attach_trace_opts;
bpf_program__expected_attach_type;
bpf_program__log_buf;
bpf_program__log_level;
Add a cookie field to the attributes of bpf_link_create(). Add bpf_program__attach_trace_opts() to attach a cookie to a link. Signed-off-by: Kui-Feng Lee <kuifeng@fb.com> --- tools/lib/bpf/bpf.c | 7 +++++++ tools/lib/bpf/bpf.h | 3 +++ tools/lib/bpf/libbpf.c | 33 +++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 12 ++++++++++++ tools/lib/bpf/libbpf.map | 1 + 5 files changed, 56 insertions(+)