Add a new helper bpf_perf_link_fill_common(), which will be used by
perf_link based tracepoint, kprobe and uprobe.
Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
---
kernel/bpf/syscall.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 6af003d..db9b500 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3306,6 +3306,40 @@ static void bpf_perf_link_dealloc(struct bpf_link *link)
kfree(perf_link);
}
+static int bpf_perf_link_fill_common(const struct perf_event *event,
+ char __user *uname, u32 ulen,
+ u64 *probe_offset, u64 *probe_addr,
+ u32 *fd_type)
+{
+ const char *buf;
+ u32 prog_id;
+ size_t len;
+ int err;
+
+ if (!ulen ^ !uname)
+ return -EINVAL;
+ if (!uname)
+ return 0;
+
+ err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf,
+ probe_offset, probe_addr);
+ if (err)
+ return err;
+
+ len = strlen(buf);
+ if (buf) {
+ err = bpf_copy_to_user(uname, buf, ulen, len);
+ if (err)
+ return err;
+ } else {
+ char zero = '\0';
+
+ if (put_user(zero, uname))
+ return -EFAULT;
+ }
+ return 0;
+}
+
static const struct bpf_link_ops bpf_perf_link_lops = {
.release = bpf_perf_link_release,
.dealloc = bpf_perf_link_dealloc,
--
1.8.3.1
