1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
|
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2018 Facebook */
#include <ctype.h>
#include <stdio.h> /* for (FILE *) used by json_writer */
#include <string.h>
#include <asm/byteorder.h>
#include <linux/bitops.h>
#include <linux/btf.h>
#include <linux/err.h>
#include "btf.h"
#include "json_writer.h"
#include "main.h"
#define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1)
#define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK)
#define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3)
#define BITS_ROUNDUP_BYTES(bits) \
(BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
__u8 bit_offset, const void *data);
static void btf_dumper_ptr(const void *data, json_writer_t *jw,
bool is_plain_text)
{
if (is_plain_text)
jsonw_printf(jw, "%p", *(unsigned long *)data);
else
jsonw_printf(jw, "%u", *(unsigned long *)data);
}
static int btf_dumper_modifier(const struct btf_dumper *d, __u32 type_id,
__u8 bit_offset, const void *data)
{
int actual_type_id;
actual_type_id = btf__resolve_type(d->btf, type_id);
if (actual_type_id < 0)
return actual_type_id;
return btf_dumper_do_type(d, actual_type_id, bit_offset, data);
}
static void btf_dumper_enum(const void *data, json_writer_t *jw)
{
jsonw_printf(jw, "%d", *(int *)data);
}
static int btf_dumper_array(const struct btf_dumper *d, __u32 type_id,
const void *data)
{
const struct btf_type *t = btf__type_by_id(d->btf, type_id);
struct btf_array *arr = (struct btf_array *)(t + 1);
long long elem_size;
int ret = 0;
__u32 i;
elem_size = btf__resolve_size(d->btf, arr->type);
if (elem_size < 0)
return elem_size;
jsonw_start_array(d->jw);
for (i = 0; i < arr->nelems; i++) {
ret = btf_dumper_do_type(d, arr->type, 0,
data + i * elem_size);
if (ret)
break;
}
jsonw_end_array(d->jw);
return ret;
}
static void btf_dumper_int_bits(__u32 int_type, __u8 bit_offset,
const void *data, json_writer_t *jw,
bool is_plain_text)
{
int left_shift_bits, right_shift_bits;
int nr_bits = BTF_INT_BITS(int_type);
int total_bits_offset;
int bytes_to_copy;
int bits_to_copy;
__u64 print_num;
total_bits_offset = bit_offset + BTF_INT_OFFSET(int_type);
data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
bit_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
bits_to_copy = bit_offset + nr_bits;
bytes_to_copy = BITS_ROUNDUP_BYTES(bits_to_copy);
print_num = 0;
memcpy(&print_num, data, bytes_to_copy);
#if defined(__BIG_ENDIAN_BITFIELD)
left_shift_bits = bit_offset;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
left_shift_bits = 64 - bits_to_copy;
#else
#error neither big nor little endian
#endif
right_shift_bits = 64 - nr_bits;
print_num <<= left_shift_bits;
print_num >>= right_shift_bits;
if (is_plain_text)
jsonw_printf(jw, "0x%llx", print_num);
else
jsonw_printf(jw, "%llu", print_num);
}
static int btf_dumper_int(const struct btf_type *t, __u8 bit_offset,
const void *data, json_writer_t *jw,
bool is_plain_text)
{
__u32 *int_type;
__u32 nr_bits;
int_type = (__u32 *)(t + 1);
nr_bits = BTF_INT_BITS(*int_type);
/* if this is bit field */
if (bit_offset || BTF_INT_OFFSET(*int_type) ||
BITS_PER_BYTE_MASKED(nr_bits)) {
btf_dumper_int_bits(*int_type, bit_offset, data, jw,
is_plain_text);
return 0;
}
switch (BTF_INT_ENCODING(*int_type)) {
case 0:
if (BTF_INT_BITS(*int_type) == 64)
jsonw_printf(jw, "%lu", *(__u64 *)data);
else if (BTF_INT_BITS(*int_type) == 32)
jsonw_printf(jw, "%u", *(__u32 *)data);
else if (BTF_INT_BITS(*int_type) == 16)
jsonw_printf(jw, "%hu", *(__u16 *)data);
else if (BTF_INT_BITS(*int_type) == 8)
jsonw_printf(jw, "%hhu", *(__u8 *)data);
else
btf_dumper_int_bits(*int_type, bit_offset, data, jw,
is_plain_text);
break;
case BTF_INT_SIGNED:
if (BTF_INT_BITS(*int_type) == 64)
jsonw_printf(jw, "%ld", *(long long *)data);
else if (BTF_INT_BITS(*int_type) == 32)
jsonw_printf(jw, "%d", *(int *)data);
else if (BTF_INT_BITS(*int_type) == 16)
jsonw_printf(jw, "%hd", *(short *)data);
else if (BTF_INT_BITS(*int_type) == 8)
jsonw_printf(jw, "%hhd", *(char *)data);
else
btf_dumper_int_bits(*int_type, bit_offset, data, jw,
is_plain_text);
break;
case BTF_INT_CHAR:
if (isprint(*(char *)data))
jsonw_printf(jw, "\"%c\"", *(char *)data);
else
if (is_plain_text)
jsonw_printf(jw, "0x%hhx", *(char *)data);
else
jsonw_printf(jw, "\"\\u00%02hhx\"",
*(char *)data);
break;
case BTF_INT_BOOL:
jsonw_bool(jw, *(int *)data);
break;
default:
/* shouldn't happen */
return -EINVAL;
}
return 0;
}
static int btf_dumper_struct(const struct btf_dumper *d, __u32 type_id,
const void *data)
{
const struct btf_type *t;
struct btf_member *m;
const void *data_off;
int ret = 0;
int i, vlen;
t = btf__type_by_id(d->btf, type_id);
if (!t)
return -EINVAL;
vlen = BTF_INFO_VLEN(t->info);
jsonw_start_object(d->jw);
m = (struct btf_member *)(t + 1);
for (i = 0; i < vlen; i++) {
data_off = data + BITS_ROUNDDOWN_BYTES(m[i].offset);
jsonw_name(d->jw, btf__name_by_offset(d->btf, m[i].name_off));
ret = btf_dumper_do_type(d, m[i].type,
BITS_PER_BYTE_MASKED(m[i].offset),
data_off);
if (ret)
break;
}
jsonw_end_object(d->jw);
return ret;
}
static int btf_dumper_do_type(const struct btf_dumper *d, __u32 type_id,
__u8 bit_offset, const void *data)
{
const struct btf_type *t = btf__type_by_id(d->btf, type_id);
switch (BTF_INFO_KIND(t->info)) {
case BTF_KIND_INT:
return btf_dumper_int(t, bit_offset, data, d->jw,
d->is_plain_text);
case BTF_KIND_STRUCT:
case BTF_KIND_UNION:
return btf_dumper_struct(d, type_id, data);
case BTF_KIND_ARRAY:
return btf_dumper_array(d, type_id, data);
case BTF_KIND_ENUM:
btf_dumper_enum(data, d->jw);
return 0;
case BTF_KIND_PTR:
btf_dumper_ptr(data, d->jw, d->is_plain_text);
return 0;
case BTF_KIND_UNKN:
jsonw_printf(d->jw, "(unknown)");
return 0;
case BTF_KIND_FWD:
/* map key or value can't be forward */
jsonw_printf(d->jw, "(fwd-kind-invalid)");
return -EINVAL;
case BTF_KIND_TYPEDEF:
case BTF_KIND_VOLATILE:
case BTF_KIND_CONST:
case BTF_KIND_RESTRICT:
return btf_dumper_modifier(d, type_id, bit_offset, data);
default:
jsonw_printf(d->jw, "(unsupported-kind");
return -EINVAL;
}
}
int btf_dumper_type(const struct btf_dumper *d, __u32 type_id,
const void *data)
{
return btf_dumper_do_type(d, type_id, 0, data);
}
|
