[PATCH bpf-next v1 1/3] bpf: Extract bpf_get_linfo_file_line

[Kumar Kartikeya Dwivedi <memxor@gmail.com>]

Extract bpf_get_linfo_file_line as its own function so that the logic to
obtain the file, line, and line number for a given program can be shared
in subsequent patches.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
---
 include/linux/bpf.h |  2 ++
 kernel/bpf/core.c   | 32 +++++++++++++++++++++++---------
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 05b34a6355b0..2c4f92085d79 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -3946,6 +3946,8 @@ static inline bool bpf_is_subprog(const struct bpf_prog *prog)
 	return prog->aux->func_idx != 0;
 }
 
+int bpf_get_linfo_file_line(struct btf *btf, const struct bpf_line_info *linfo,
+			    const char **filep, const char **linep, int *nump);
 int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char **filep,
 			   const char **linep, int *nump);
 struct bpf_prog *bpf_prog_find_from_stack(void);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 1af5fb3f21d9..052dd78a2d81 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -3313,6 +3313,28 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_bulk_tx);
 
 #ifdef CONFIG_BPF_SYSCALL
 
+int bpf_get_linfo_file_line(struct btf *btf, const struct bpf_line_info *linfo,
+			    const char **filep, const char **linep, int *nump)
+{
+	/* Get base component of the file path. */
+	if (filep) {
+		*filep = btf_name_by_offset(btf, linfo->file_name_off);
+		*filep = kbasename(*filep);
+	}
+
+	/* Obtain the source line, and strip whitespace in prefix. */
+	if (linep) {
+		*linep = btf_name_by_offset(btf, linfo->line_off);
+		while (isspace(**linep))
+			*linep += 1;
+	}
+
+	if (nump)
+		*nump = BPF_LINE_INFO_LINE_NUM(linfo->line_col);
+
+	return 0;
+}
+
 int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char **filep,
 			   const char **linep, int *nump)
 {
@@ -3347,15 +3369,7 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char *
 	if (idx == -1)
 		return -ENOENT;
 
-	/* Get base component of the file path. */
-	*filep = btf_name_by_offset(btf, linfo[idx].file_name_off);
-	*filep = kbasename(*filep);
-	/* Obtain the source line, and strip whitespace in prefix. */
-	*linep = btf_name_by_offset(btf, linfo[idx].line_off);
-	while (isspace(**linep))
-		*linep += 1;
-	*nump = BPF_LINE_INFO_LINE_NUM(linfo[idx].line_col);
-	return 0;
+	return bpf_get_linfo_file_line(btf, &linfo[idx], filep, linep, nump);
 }
 
 struct walk_stack_ctx {
-- 
2.52.0