change system file

hc

2024-10-09 244b2c5ca8b14627e4a17755e5922221e121c771

 kernel/tools/bpf/bpftool/btf_dumper.c
..
..
@@ -1,15 +1,17 @@
1
-// SPDX-License-Identifier: GPL-2.0
1
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2
2
 /* Copyright (c) 2018 Facebook */
3
3
 
4
4
 #include <ctype.h>
5
5
 #include <stdio.h> /* for (FILE *) used by json_writer */
6
6
 #include <string.h>
7
+#include <unistd.h>
7
8
 #include <asm/byteorder.h>
8
9
 #include <linux/bitops.h>
9
10
 #include <linux/btf.h>
10
11
 #include <linux/err.h>
12
+#include <bpf/btf.h>
13
+#include <bpf/bpf.h>
11
14
 
12
-#include "btf.h"
13
15
 #include "json_writer.h"
14
16
 #include "main.h"
15
17
 
..
..
@@ -22,13 +24,102 @@
22
24
 static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
23
25
 			      __u8 bit_offset, const void *data);
24
26
 
25
-static void btf_dumper_ptr(const void *data, json_writer_t *jw,
26
-			   bool is_plain_text)
27
+static int btf_dump_func(const struct btf *btf, char *func_sig,
28
+			 const struct btf_type *func_proto,
29
+			 const struct btf_type *func, int pos, int size);
30
+
31
+static int dump_prog_id_as_func_ptr(const struct btf_dumper *d,
32
+				    const struct btf_type *func_proto,
33
+				    __u32 prog_id)
27
34
 {
28
-	if (is_plain_text)
29
-		jsonw_printf(jw, "%p", *(void **)data);
35
+	struct bpf_prog_info_linear *prog_info = NULL;
36
+	const struct btf_type *func_type;
37
+	const char *prog_name = NULL;
38
+	struct bpf_func_info *finfo;
39
+	struct btf *prog_btf = NULL;
40
+	struct bpf_prog_info *info;
41
+	int prog_fd, func_sig_len;
42
+	char prog_str[1024];
43
+
44
+	/* Get the ptr's func_proto */
45
+	func_sig_len = btf_dump_func(d->btf, prog_str, func_proto, NULL, 0,
46
+				     sizeof(prog_str));
47
+	if (func_sig_len == -1)
48
+		return -1;
49
+
50
+	if (!prog_id)
51
+		goto print;
52
+
53
+	/* Get the bpf_prog's name.  Obtain from func_info. */
54
+	prog_fd = bpf_prog_get_fd_by_id(prog_id);
55
+	if (prog_fd == -1)
56
+		goto print;
57
+
58
+	prog_info = bpf_program__get_prog_info_linear(prog_fd,
59
+						1UL << BPF_PROG_INFO_FUNC_INFO);
60
+	close(prog_fd);
61
+	if (IS_ERR(prog_info)) {
62
+		prog_info = NULL;
63
+		goto print;
64
+	}
65
+	info = &prog_info->info;
66
+
67
+	if (!info->btf_id || !info->nr_func_info ||
68
+	    btf__get_from_id(info->btf_id, &prog_btf))
69
+		goto print;
70
+	finfo = u64_to_ptr(info->func_info);
71
+	func_type = btf__type_by_id(prog_btf, finfo->type_id);
72
+	if (!func_type || !btf_is_func(func_type))
73
+		goto print;
74
+
75
+	prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
76
+
77
+print:
78
+	if (!prog_id)
79
+		snprintf(&prog_str[func_sig_len],
80
+			 sizeof(prog_str) - func_sig_len, " 0");
81
+	else if (prog_name)
82
+		snprintf(&prog_str[func_sig_len],
83
+			 sizeof(prog_str) - func_sig_len,
84
+			 " %s/prog_id:%u", prog_name, prog_id);
30
85
 	else
31
-		jsonw_printf(jw, "%lu", *(unsigned long *)data);
86
+		snprintf(&prog_str[func_sig_len],
87
+			 sizeof(prog_str) - func_sig_len,
88
+			 " <unknown_prog_name>/prog_id:%u", prog_id);
89
+
90
+	prog_str[sizeof(prog_str) - 1] = '\0';
91
+	jsonw_string(d->jw, prog_str);
92
+	btf__free(prog_btf);
93
+	free(prog_info);
94
+	return 0;
95
+}
96
+
97
+static void btf_dumper_ptr(const struct btf_dumper *d,
98
+			   const struct btf_type *t,
99
+			   const void *data)
100
+{
101
+	unsigned long value = *(unsigned long *)data;
102
+	const struct btf_type *ptr_type;
103
+	__s32 ptr_type_id;
104
+
105
+	if (!d->prog_id_as_func_ptr || value > UINT32_MAX)
106
+		goto print_ptr_value;
107
+
108
+	ptr_type_id = btf__resolve_type(d->btf, t->type);
109
+	if (ptr_type_id < 0)
110
+		goto print_ptr_value;
111
+	ptr_type = btf__type_by_id(d->btf, ptr_type_id);
112
+	if (!ptr_type || !btf_is_func_proto(ptr_type))
113
+		goto print_ptr_value;
114
+
115
+	if (!dump_prog_id_as_func_ptr(d, ptr_type, value))
116
+		return;
117
+
118
+print_ptr_value:
119
+	if (d->is_plain_text)
120
+		jsonw_printf(d->jw, "%p", (void *)value);
121
+	else
122
+		jsonw_printf(d->jw, "%lu", value);
32
123
 }
33
124
 
34
125
 static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id,
..
..
@@ -43,9 +134,78 @@
43
134
 	return btf_dumper_do_type(d, actual_type_id, bit_offset, data);
44
135
 }
45
136
 
46
-static void btf_dumper_enum(const void *data, json_writer_t *jw)
137
+static int btf_dumper_enum(const struct btf_dumper *d,
138
+			    const struct btf_type *t,
139
+			    const void *data)
47
140
 {
48
-	jsonw_printf(jw, "%d", *(int *)data);
141
+	const struct btf_enum *enums = btf_enum(t);
142
+	__s64 value;
143
+	__u16 i;
144
+
145
+	switch (t->size) {
146
+	case 8:
147
+		value = *(__s64 *)data;
148
+		break;
149
+	case 4:
150
+		value = *(__s32 *)data;
151
+		break;
152
+	case 2:
153
+		value = *(__s16 *)data;
154
+		break;
155
+	case 1:
156
+		value = *(__s8 *)data;
157
+		break;
158
+	default:
159
+		return -EINVAL;
160
+	}
161
+
162
+	for (i = 0; i < btf_vlen(t); i++) {
163
+		if (value == enums[i].val) {
164
+			jsonw_string(d->jw,
165
+				     btf__name_by_offset(d->btf,
166
+							 enums[i].name_off));
167
+			return 0;
168
+		}
169
+	}
170
+
171
+	jsonw_int(d->jw, value);
172
+	return 0;
173
+}
174
+
175
+static bool is_str_array(const struct btf *btf, const struct btf_array *arr,
176
+			 const char *s)
177
+{
178
+	const struct btf_type *elem_type;
179
+	const char *end_s;
180
+
181
+	if (!arr->nelems)
182
+		return false;
183
+
184
+	elem_type = btf__type_by_id(btf, arr->type);
185
+	/* Not skipping typedef.  typedef to char does not count as
186
+	 * a string now.
187
+	 */
188
+	while (elem_type && btf_is_mod(elem_type))
189
+		elem_type = btf__type_by_id(btf, elem_type->type);
190
+
191
+	if (!elem_type || !btf_is_int(elem_type) || elem_type->size != 1)
192
+		return false;
193
+
194
+	if (btf_int_encoding(elem_type) != BTF_INT_CHAR &&
195
+	    strcmp("char", btf__name_by_offset(btf, elem_type->name_off)))
196
+		return false;
197
+
198
+	end_s = s + arr->nelems;
199
+	while (s < end_s) {
200
+		if (!*s)
201
+			return true;
202
+		if (*s <= 0x1f || *s >= 0x7f)
203
+			return false;
204
+		s++;
205
+	}
206
+
207
+	/* '\0' is not found */
208
+	return false;
49
209
 }
50
210
 
51
211
 static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id,
..
..
@@ -56,6 +216,11 @@
56
216
 	long long elem_size;
57
217
 	int ret = 0;
58
218
 	__u32 i;
219
+
220
+	if (is_str_array(d->btf, arr, data)) {
221
+		jsonw_string(d->jw, data);
222
+		return 0;
223
+	}
59
224
 
60
225
 	elem_size = btf__resolve_size(d->btf, arr->type);
61
226
 	if (elem_size < 0)
..
..
@@ -73,40 +238,122 @@
73
238
 	return ret;
74
239
 }
75
240
 
76
-static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset,
241
+static void btf_int128_print(json_writer_t *jw, const void *data,
242
+			     bool is_plain_text)
243
+{
244
+	/* data points to a __int128 number.
245
+	 * Suppose
246
+	 *     int128_num = *(__int128 *)data;
247
+	 * The below formulas shows what upper_num and lower_num represents:
248
+	 *     upper_num = int128_num >> 64;
249
+	 *     lower_num = int128_num & 0xffffffffFFFFFFFFULL;
250
+	 */
251
+	__u64 upper_num, lower_num;
252
+
253
+#ifdef __BIG_ENDIAN_BITFIELD
254
+	upper_num = *(__u64 *)data;
255
+	lower_num = *(__u64 *)(data + 8);
256
+#else
257
+	upper_num = *(__u64 *)(data + 8);
258
+	lower_num = *(__u64 *)data;
259
+#endif
260
+
261
+	if (is_plain_text) {
262
+		if (upper_num == 0)
263
+			jsonw_printf(jw, "0x%llx", lower_num);
264
+		else
265
+			jsonw_printf(jw, "0x%llx%016llx", upper_num, lower_num);
266
+	} else {
267
+		if (upper_num == 0)
268
+			jsonw_printf(jw, "\"0x%llx\"", lower_num);
269
+		else
270
+			jsonw_printf(jw, "\"0x%llx%016llx\"", upper_num, lower_num);
271
+	}
272
+}
273
+
274
+static void btf_int128_shift(__u64 *print_num, __u16 left_shift_bits,
275
+			     __u16 right_shift_bits)
276
+{
277
+	__u64 upper_num, lower_num;
278
+
279
+#ifdef __BIG_ENDIAN_BITFIELD
280
+	upper_num = print_num[0];
281
+	lower_num = print_num[1];
282
+#else
283
+	upper_num = print_num[1];
284
+	lower_num = print_num[0];
285
+#endif
286
+
287
+	/* shake out un-needed bits by shift/or operations */
288
+	if (left_shift_bits >= 64) {
289
+		upper_num = lower_num << (left_shift_bits - 64);
290
+		lower_num = 0;
291
+	} else {
292
+		upper_num = (upper_num << left_shift_bits) |
293
+			    (lower_num >> (64 - left_shift_bits));
294
+		lower_num = lower_num << left_shift_bits;
295
+	}
296
+
297
+	if (right_shift_bits >= 64) {
298
+		lower_num = upper_num >> (right_shift_bits - 64);
299
+		upper_num = 0;
300
+	} else {
301
+		lower_num = (lower_num >> right_shift_bits) |
302
+			    (upper_num << (64 - right_shift_bits));
303
+		upper_num = upper_num >> right_shift_bits;
304
+	}
305
+
306
+#ifdef __BIG_ENDIAN_BITFIELD
307
+	print_num[0] = upper_num;
308
+	print_num[1] = lower_num;
309
+#else
310
+	print_num[0] = lower_num;
311
+	print_num[1] = upper_num;
312
+#endif
313
+}
314
+
315
+static void btf_dumper_bitfield(__u32 nr_bits, __u8 bit_offset,
77
316
 				const void *data, json_writer_t *jw,
78
317
 				bool is_plain_text)
79
318
 {
80
319
 	int left_shift_bits, right_shift_bits;
81
-	int nr_bits = BTF_INT_BITS(int_type);
82
-	int total_bits_offset;
320
+	__u64 print_num[2] = {};
83
321
 	int bytes_to_copy;
84
322
 	int bits_to_copy;
85
-	__u64 print_num;
86
323
 
87
-	total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type);
88
-	data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
89
-	bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
90
324
 	bits_to_copy = bit_offset + nr_bits;
91
325
 	bytes_to_copy = BITS_ROUNDUP_BYTES(bits_to_copy);
92
326
 
93
-	print_num = 0;
94
-	memcpy(&print_num, data, bytes_to_copy);
327
+	memcpy(print_num, data, bytes_to_copy);
95
328
 #if defined(__BIG_ENDIAN_BITFIELD)
96
329
 	left_shift_bits = bit_offset;
97
330
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
98
-	left_shift_bits = 64 - bits_to_copy;
331
+	left_shift_bits = 128 - bits_to_copy;
99
332
 #else
100
333
 #error neither big nor little endian
101
334
 #endif
102
-	right_shift_bits = 64 - nr_bits;
335
+	right_shift_bits = 128 - nr_bits;
103
336
 
104
-	print_num <<= left_shift_bits;
105
-	print_num >>= right_shift_bits;
106
-	if (is_plain_text)
107
-		jsonw_printf(jw, "0x%llx", print_num);
108
-	else
109
-		jsonw_printf(jw, "%llu", print_num);
337
+	btf_int128_shift(print_num, left_shift_bits, right_shift_bits);
338
+	btf_int128_print(jw, print_num, is_plain_text);
339
+}
340
+
341
+
342
+static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset,
343
+				const void *data, json_writer_t *jw,
344
+				bool is_plain_text)
345
+{
346
+	int nr_bits = BTF_INT_BITS(int_type);
347
+	int total_bits_offset;
348
+
349
+	/* bits_offset is at most 7.
350
+	 * BTF_INT_OFFSET() cannot exceed 128 bits.
351
+	 */
352
+	total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type);
353
+	data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
354
+	bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
355
+	btf_dumper_bitfield(nr_bits, bit_offset, data, jw,
356
+			    is_plain_text);
110
357
 }
111
358
 
112
359
 static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset,
..
..
@@ -123,6 +370,11 @@
123
370
 	    BITS_PER_BYTE_MASKED(nr_bits)) {
124
371
 		btf_dumper_int_bits(*int_type, bit_offset, data, jw,
125
372
 				    is_plain_text);
373
+		return 0;
374
+	}
375
+
376
+	if (nr_bits == 128) {
377
+		btf_int128_print(jw, data, is_plain_text);
126
378
 		return 0;
127
379
 	}
128
380
 
..
..
@@ -164,7 +416,7 @@
164
416
 					     *(char *)data);
165
417
 		break;
166
418
 	case BTF_INT_BOOL:
167
-		jsonw_bool(jw, *(int *)data);
419
+		jsonw_bool(jw, *(bool *)data);
168
420
 		break;
169
421
 	default:
170
422
 		/* shouldn't happen */
..
..
@@ -180,6 +432,7 @@
180
432
 	const struct btf_type *t;
181
433
 	struct btf_member *m;
182
434
 	const void *data_off;
435
+	int kind_flag;
183
436
 	int ret = 0;
184
437
 	int i, vlen;
185
438
 
..
..
@@ -187,20 +440,77 @@
187
440
 	if (!t)
188
441
 		return -EINVAL;
189
442
 
443
+	kind_flag = BTF_INFO_KFLAG(t->info);
190
444
 	vlen = BTF_INFO_VLEN(t->info);
191
445
 	jsonw_start_object(d->jw);
192
446
 	m = (struct btf_member *)(t + 1);
193
447
 
194
448
 	for (i = 0; i < vlen; i++) {
195
-		data_off = data + BITS_ROUNDDOWN_BYTES(m[i].offset);
449
+		__u32 bit_offset = m[i].offset;
450
+		__u32 bitfield_size = 0;
451
+
452
+		if (kind_flag) {
453
+			bitfield_size = BTF_MEMBER_BITFIELD_SIZE(bit_offset);
454
+			bit_offset = BTF_MEMBER_BIT_OFFSET(bit_offset);
455
+		}
456
+
196
457
 		jsonw_name(d->jw, btf__name_by_offset(d->btf, m[i].name_off));
197
-		ret = btf_dumper_do_type(d, m[i].type,
198
-					 BITS_PER_BYTE_MASKED(m[i].offset),
199
-					 data_off);
458
+		data_off = data + BITS_ROUNDDOWN_BYTES(bit_offset);
459
+		if (bitfield_size) {
460
+			btf_dumper_bitfield(bitfield_size,
461
+					    BITS_PER_BYTE_MASKED(bit_offset),
462
+					    data_off, d->jw, d->is_plain_text);
463
+		} else {
464
+			ret = btf_dumper_do_type(d, m[i].type,
465
+						 BITS_PER_BYTE_MASKED(bit_offset),
466
+						 data_off);
467
+			if (ret)
468
+				break;
469
+		}
470
+	}
471
+
472
+	jsonw_end_object(d->jw);
473
+
474
+	return ret;
475
+}
476
+
477
+static int btf_dumper_var(const struct btf_dumper *d, __u32 type_id,
478
+			  __u8 bit_offset, const void *data)
479
+{
480
+	const struct btf_type *t = btf__type_by_id(d->btf, type_id);
481
+	int ret;
482
+
483
+	jsonw_start_object(d->jw);
484
+	jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off));
485
+	ret = btf_dumper_do_type(d, t->type, bit_offset, data);
486
+	jsonw_end_object(d->jw);
487
+
488
+	return ret;
489
+}
490
+
491
+static int btf_dumper_datasec(const struct btf_dumper *d, __u32 type_id,
492
+			      const void *data)
493
+{
494
+	struct btf_var_secinfo *vsi;
495
+	const struct btf_type *t;
496
+	int ret = 0, i, vlen;
497
+
498
+	t = btf__type_by_id(d->btf, type_id);
499
+	if (!t)
500
+		return -EINVAL;
501
+
502
+	vlen = BTF_INFO_VLEN(t->info);
503
+	vsi = (struct btf_var_secinfo *)(t + 1);
504
+
505
+	jsonw_start_object(d->jw);
506
+	jsonw_name(d->jw, btf__name_by_offset(d->btf, t->name_off));
507
+	jsonw_start_array(d->jw);
508
+	for (i = 0; i < vlen; i++) {
509
+		ret = btf_dumper_do_type(d, vsi[i].type, 0, data + vsi[i].offset);
200
510
 		if (ret)
201
511
 			break;
202
512
 	}
203
-
513
+	jsonw_end_array(d->jw);
204
514
 	jsonw_end_object(d->jw);
205
515
 
206
516
 	return ret;
..
..
@@ -221,10 +531,9 @@
221
531
 	case BTF_KIND_ARRAY:
222
532
 		return btf_dumper_array(d, type_id, data);
223
533
 	case BTF_KIND_ENUM:
224
-		btf_dumper_enum(data, d->jw);
225
-		return 0;
534
+		return btf_dumper_enum(d, t, data);
226
535
 	case BTF_KIND_PTR:
227
-		btf_dumper_ptr(data, d->jw, d->is_plain_text);
536
+		btf_dumper_ptr(d, t, data);
228
537
 		return 0;
229
538
 	case BTF_KIND_UNKN:
230
539
 		jsonw_printf(d->jw, "(unknown)");
..
..
@@ -238,6 +547,10 @@
238
547
 	case BTF_KIND_CONST:
239
548
 	case BTF_KIND_RESTRICT:
240
549
 		return btf_dumper_modifier(d, type_id, bit_offset, data);
550
+	case BTF_KIND_VAR:
551
+		return btf_dumper_var(d, type_id, bit_offset, data);
552
+	case BTF_KIND_DATASEC:
553
+		return btf_dumper_datasec(d, type_id, data);
241
554
 	default:
242
555
 		jsonw_printf(d->jw, "(unsupported-kind");
243
556
 		return -EINVAL;
..
..
@@ -249,3 +562,222 @@
249
562
 {
250
563
 	return btf_dumper_do_type(d, type_id, 0, data);
251
564
 }
565
+
566
+#define BTF_PRINT_ARG(...)						\
567
+	do {								\
568
+		pos += snprintf(func_sig + pos, size - pos,		\
569
+				__VA_ARGS__);				\
570
+		if (pos >= size)					\
571
+			return -1;					\
572
+	} while (0)
573
+#define BTF_PRINT_TYPE(type)					\
574
+	do {								\
575
+		pos = __btf_dumper_type_only(btf, type, func_sig,	\
576
+					     pos, size);		\
577
+		if (pos == -1)						\
578
+			return -1;					\
579
+	} while (0)
580
+
581
+static int __btf_dumper_type_only(const struct btf *btf, __u32 type_id,
582
+				  char *func_sig, int pos, int size)
583
+{
584
+	const struct btf_type *proto_type;
585
+	const struct btf_array *array;
586
+	const struct btf_var *var;
587
+	const struct btf_type *t;
588
+
589
+	if (!type_id) {
590
+		BTF_PRINT_ARG("void ");
591
+		return pos;
592
+	}
593
+
594
+	t = btf__type_by_id(btf, type_id);
595
+
596
+	switch (BTF_INFO_KIND(t->info)) {
597
+	case BTF_KIND_INT:
598
+	case BTF_KIND_TYPEDEF:
599
+		BTF_PRINT_ARG("%s ", btf__name_by_offset(btf, t->name_off));
600
+		break;
601
+	case BTF_KIND_STRUCT:
602
+		BTF_PRINT_ARG("struct %s ",
603
+			      btf__name_by_offset(btf, t->name_off));
604
+		break;
605
+	case BTF_KIND_UNION:
606
+		BTF_PRINT_ARG("union %s ",
607
+			      btf__name_by_offset(btf, t->name_off));
608
+		break;
609
+	case BTF_KIND_ENUM:
610
+		BTF_PRINT_ARG("enum %s ",
611
+			      btf__name_by_offset(btf, t->name_off));
612
+		break;
613
+	case BTF_KIND_ARRAY:
614
+		array = (struct btf_array *)(t + 1);
615
+		BTF_PRINT_TYPE(array->type);
616
+		BTF_PRINT_ARG("[%d]", array->nelems);
617
+		break;
618
+	case BTF_KIND_PTR:
619
+		BTF_PRINT_TYPE(t->type);
620
+		BTF_PRINT_ARG("* ");
621
+		break;
622
+	case BTF_KIND_FWD:
623
+		BTF_PRINT_ARG("%s %s ",
624
+			      BTF_INFO_KFLAG(t->info) ? "union" : "struct",
625
+			      btf__name_by_offset(btf, t->name_off));
626
+		break;
627
+	case BTF_KIND_VOLATILE:
628
+		BTF_PRINT_ARG("volatile ");
629
+		BTF_PRINT_TYPE(t->type);
630
+		break;
631
+	case BTF_KIND_CONST:
632
+		BTF_PRINT_ARG("const ");
633
+		BTF_PRINT_TYPE(t->type);
634
+		break;
635
+	case BTF_KIND_RESTRICT:
636
+		BTF_PRINT_ARG("restrict ");
637
+		BTF_PRINT_TYPE(t->type);
638
+		break;
639
+	case BTF_KIND_FUNC_PROTO:
640
+		pos = btf_dump_func(btf, func_sig, t, NULL, pos, size);
641
+		if (pos == -1)
642
+			return -1;
643
+		break;
644
+	case BTF_KIND_FUNC:
645
+		proto_type = btf__type_by_id(btf, t->type);
646
+		pos = btf_dump_func(btf, func_sig, proto_type, t, pos, size);
647
+		if (pos == -1)
648
+			return -1;
649
+		break;
650
+	case BTF_KIND_VAR:
651
+		var = (struct btf_var *)(t + 1);
652
+		if (var->linkage == BTF_VAR_STATIC)
653
+			BTF_PRINT_ARG("static ");
654
+		BTF_PRINT_TYPE(t->type);
655
+		BTF_PRINT_ARG(" %s",
656
+			      btf__name_by_offset(btf, t->name_off));
657
+		break;
658
+	case BTF_KIND_DATASEC:
659
+		BTF_PRINT_ARG("section (\"%s\") ",
660
+			      btf__name_by_offset(btf, t->name_off));
661
+		break;
662
+	case BTF_KIND_UNKN:
663
+	default:
664
+		return -1;
665
+	}
666
+
667
+	return pos;
668
+}
669
+
670
+static int btf_dump_func(const struct btf *btf, char *func_sig,
671
+			 const struct btf_type *func_proto,
672
+			 const struct btf_type *func, int pos, int size)
673
+{
674
+	int i, vlen;
675
+
676
+	BTF_PRINT_TYPE(func_proto->type);
677
+	if (func)
678
+		BTF_PRINT_ARG("%s(", btf__name_by_offset(btf, func->name_off));
679
+	else
680
+		BTF_PRINT_ARG("(");
681
+	vlen = BTF_INFO_VLEN(func_proto->info);
682
+	for (i = 0; i < vlen; i++) {
683
+		struct btf_param *arg = &((struct btf_param *)(func_proto + 1))[i];
684
+
685
+		if (i)
686
+			BTF_PRINT_ARG(", ");
687
+		if (arg->type) {
688
+			BTF_PRINT_TYPE(arg->type);
689
+			if (arg->name_off)
690
+				BTF_PRINT_ARG("%s",
691
+					      btf__name_by_offset(btf, arg->name_off));
692
+			else if (pos && func_sig[pos - 1] == ' ')
693
+				/* Remove unnecessary space for
694
+				 * FUNC_PROTO that does not have
695
+				 * arg->name_off
696
+				 */
697
+				func_sig[--pos] = '\0';
698
+		} else {
699
+			BTF_PRINT_ARG("...");
700
+		}
701
+	}
702
+	BTF_PRINT_ARG(")");
703
+
704
+	return pos;
705
+}
706
+
707
+void btf_dumper_type_only(const struct btf *btf, __u32 type_id, char *func_sig,
708
+			  int size)
709
+{
710
+	int err;
711
+
712
+	func_sig[0] = '\0';
713
+	if (!btf)
714
+		return;
715
+
716
+	err = __btf_dumper_type_only(btf, type_id, func_sig, 0, size);
717
+	if (err < 0)
718
+		func_sig[0] = '\0';
719
+}
720
+
721
+static const char *ltrim(const char *s)
722
+{
723
+	while (isspace(*s))
724
+		s++;
725
+
726
+	return s;
727
+}
728
+
729
+void btf_dump_linfo_plain(const struct btf *btf,
730
+			  const struct bpf_line_info *linfo,
731
+			  const char *prefix, bool linum)
732
+{
733
+	const char *line = btf__name_by_offset(btf, linfo->line_off);
734
+
735
+	if (!line)
736
+		return;
737
+	line = ltrim(line);
738
+
739
+	if (!prefix)
740
+		prefix = "";
741
+
742
+	if (linum) {
743
+		const char *file = btf__name_by_offset(btf, linfo->file_name_off);
744
+
745
+		/* More forgiving on file because linum option is
746
+		 * expected to provide more info than the already
747
+		 * available src line.
748
+		 */
749
+		if (!file)
750
+			file = "";
751
+
752
+		printf("%s%s [file:%s line_num:%u line_col:%u]\n",
753
+		       prefix, line, file,
754
+		       BPF_LINE_INFO_LINE_NUM(linfo->line_col),
755
+		       BPF_LINE_INFO_LINE_COL(linfo->line_col));
756
+	} else {
757
+		printf("%s%s\n", prefix, line);
758
+	}
759
+}
760
+
761
+void btf_dump_linfo_json(const struct btf *btf,
762
+			 const struct bpf_line_info *linfo, bool linum)
763
+{
764
+	const char *line = btf__name_by_offset(btf, linfo->line_off);
765
+
766
+	if (line)
767
+		jsonw_string_field(json_wtr, "src", ltrim(line));
768
+
769
+	if (linum) {
770
+		const char *file = btf__name_by_offset(btf, linfo->file_name_off);
771
+
772
+		if (file)
773
+			jsonw_string_field(json_wtr, "file", file);
774
+
775
+		if (BPF_LINE_INFO_LINE_NUM(linfo->line_col))
776
+			jsonw_int_field(json_wtr, "line_num",
777
+					BPF_LINE_INFO_LINE_NUM(linfo->line_col));
778
+
779
+		if (BPF_LINE_INFO_LINE_COL(linfo->line_col))
780
+			jsonw_int_field(json_wtr, "line_col",
781
+					BPF_LINE_INFO_LINE_COL(linfo->line_col));
782
+	}
783
+}