Commit | Line | Data |
---|---|---|
0ae3cfc6 SM |
1 | /* |
2 | * Copyright 2020 EfficiOS, Inc. | |
3 | * | |
4 | * SPDX-License-Identifier: GPL-2.0-only | |
5 | * | |
6 | */ | |
7 | ||
8 | #include "bytecode.h" | |
9 | ||
10 | #include <errno.h> | |
11 | ||
12 | #include "common/align.h" | |
13 | ||
14 | #define INIT_ALLOC_SIZE 4 | |
15 | ||
16 | static inline int get_count_order(unsigned int count) | |
17 | { | |
18 | int order; | |
19 | ||
20 | order = lttng_fls(count) - 1; | |
21 | if (count & (count - 1)) | |
22 | order++; | |
23 | return order; | |
24 | } | |
25 | ||
26 | LTTNG_HIDDEN | |
2b00d462 | 27 | int bytecode_init(struct lttng_bytecode_alloc **fb) |
0ae3cfc6 SM |
28 | { |
29 | uint32_t alloc_len; | |
30 | ||
2b00d462 | 31 | alloc_len = sizeof(struct lttng_bytecode_alloc) + INIT_ALLOC_SIZE; |
0ae3cfc6 SM |
32 | *fb = calloc(alloc_len, 1); |
33 | if (!*fb) { | |
34 | return -ENOMEM; | |
35 | } else { | |
36 | (*fb)->alloc_len = alloc_len; | |
37 | return 0; | |
38 | } | |
39 | } | |
40 | ||
41 | LTTNG_HIDDEN | |
2b00d462 | 42 | int32_t bytecode_reserve(struct lttng_bytecode_alloc **fb, uint32_t align, uint32_t len) |
0ae3cfc6 SM |
43 | { |
44 | int32_t ret; | |
45 | uint32_t padding = offset_align((*fb)->b.len, align); | |
46 | uint32_t new_len = (*fb)->b.len + padding + len; | |
2b00d462 | 47 | uint32_t new_alloc_len = sizeof(struct lttng_bytecode_alloc) + new_len; |
0ae3cfc6 SM |
48 | uint32_t old_alloc_len = (*fb)->alloc_len; |
49 | ||
50 | if (new_len > LTTNG_FILTER_MAX_LEN) | |
51 | return -EINVAL; | |
52 | ||
53 | if (new_alloc_len > old_alloc_len) { | |
2b00d462 | 54 | struct lttng_bytecode_alloc *newptr; |
0ae3cfc6 SM |
55 | |
56 | new_alloc_len = | |
57 | max_t(uint32_t, 1U << get_count_order(new_alloc_len), old_alloc_len << 1); | |
58 | newptr = realloc(*fb, new_alloc_len); | |
59 | if (!newptr) | |
60 | return -ENOMEM; | |
61 | *fb = newptr; | |
62 | /* We zero directly the memory from start of allocation. */ | |
63 | memset(&((char *) *fb)[old_alloc_len], 0, new_alloc_len - old_alloc_len); | |
64 | (*fb)->alloc_len = new_alloc_len; | |
65 | } | |
66 | (*fb)->b.len += padding; | |
67 | ret = (*fb)->b.len; | |
68 | (*fb)->b.len += len; | |
69 | return ret; | |
70 | } | |
71 | ||
72 | LTTNG_HIDDEN | |
2b00d462 | 73 | int bytecode_push(struct lttng_bytecode_alloc **fb, const void *data, |
0ae3cfc6 SM |
74 | uint32_t align, uint32_t len) |
75 | { | |
76 | int32_t offset; | |
77 | ||
78 | offset = bytecode_reserve(fb, align, len); | |
79 | if (offset < 0) | |
80 | return offset; | |
81 | memcpy(&(*fb)->b.data[offset], data, len); | |
82 | return 0; | |
83 | } | |
84 | ||
85 | LTTNG_HIDDEN | |
2b00d462 | 86 | int bytecode_push_logical(struct lttng_bytecode_alloc **fb, |
0ae3cfc6 SM |
87 | struct logical_op *data, |
88 | uint32_t align, uint32_t len, | |
89 | uint16_t *skip_offset) | |
90 | { | |
91 | int32_t offset; | |
92 | ||
93 | offset = bytecode_reserve(fb, align, len); | |
94 | if (offset < 0) | |
95 | return offset; | |
96 | memcpy(&(*fb)->b.data[offset], data, len); | |
97 | *skip_offset = | |
98 | (void *) &((struct logical_op *) &(*fb)->b.data[offset])->skip_offset | |
99 | - (void *) &(*fb)->b.data[0]; | |
100 | return 0; | |
101 | } | |
763f0d4c | 102 | |
6afbab01 SM |
103 | LTTNG_HIDDEN |
104 | int bytecode_push_get_payload_root(struct lttng_bytecode_alloc **bytecode) | |
105 | { | |
106 | int ret; | |
107 | struct load_op *insn; | |
108 | const uint32_t insn_len = sizeof(struct load_op); | |
109 | ||
110 | insn = calloc(insn_len, 1); | |
111 | if (!insn) { | |
112 | ret = -ENOMEM; | |
113 | goto end; | |
114 | } | |
115 | ||
116 | insn->op = BYTECODE_OP_GET_PAYLOAD_ROOT; | |
117 | ret = bytecode_push(bytecode, insn, 1, insn_len); | |
118 | free(insn); | |
119 | end: | |
120 | return ret; | |
121 | } | |
122 | ||
123 | LTTNG_HIDDEN | |
124 | int bytecode_push_get_context_root(struct lttng_bytecode_alloc **bytecode) | |
125 | { | |
126 | int ret; | |
127 | struct load_op *insn; | |
128 | const uint32_t insn_len = sizeof(struct load_op); | |
129 | ||
130 | insn = calloc(insn_len, 1); | |
131 | if (!insn) { | |
132 | ret = -ENOMEM; | |
133 | goto end; | |
134 | } | |
135 | ||
136 | insn->op = BYTECODE_OP_GET_CONTEXT_ROOT; | |
137 | ret = bytecode_push(bytecode, insn, 1, insn_len); | |
138 | free(insn); | |
139 | end: | |
140 | return ret; | |
141 | } | |
142 | ||
143 | LTTNG_HIDDEN | |
144 | int bytecode_push_get_app_context_root(struct lttng_bytecode_alloc **bytecode) | |
145 | { | |
146 | int ret; | |
147 | struct load_op *insn; | |
148 | const uint32_t insn_len = sizeof(struct load_op); | |
149 | ||
150 | insn = calloc(insn_len, 1); | |
151 | if (!insn) { | |
152 | ret = -ENOMEM; | |
153 | goto end; | |
154 | } | |
155 | ||
156 | insn->op = BYTECODE_OP_GET_APP_CONTEXT_ROOT; | |
157 | ret = bytecode_push(bytecode, insn, 1, insn_len); | |
158 | free(insn); | |
159 | end: | |
160 | return ret; | |
161 | } | |
162 | ||
163 | LTTNG_HIDDEN | |
164 | int bytecode_push_get_index_u64(struct lttng_bytecode_alloc **bytecode, | |
165 | uint64_t index) | |
166 | { | |
167 | int ret; | |
168 | struct load_op *insn; | |
169 | struct get_index_u64 index_op_data; | |
170 | const uint32_t insn_len = | |
171 | sizeof(struct load_op) + sizeof(struct get_index_u64); | |
172 | ||
173 | insn = calloc(insn_len, 1); | |
174 | if (!insn) { | |
175 | ret = -ENOMEM; | |
176 | goto end; | |
177 | } | |
178 | ||
179 | insn->op = BYTECODE_OP_GET_INDEX_U64; | |
180 | index_op_data.index = index; | |
181 | memcpy(insn->data, &index_op_data, sizeof(index)); | |
182 | ret = bytecode_push(bytecode, insn, 1, insn_len); | |
183 | ||
184 | free(insn); | |
185 | end: | |
186 | return ret; | |
187 | } | |
188 | ||
189 | LTTNG_HIDDEN | |
190 | int bytecode_push_get_symbol(struct lttng_bytecode_alloc **bytecode, | |
191 | struct lttng_bytecode_alloc **bytecode_reloc, | |
192 | const char *symbol) | |
193 | { | |
194 | int ret; | |
195 | struct load_op *insn; | |
196 | struct get_symbol symbol_offset; | |
197 | uint32_t reloc_offset_u32; | |
198 | uint16_t reloc_offset; | |
199 | uint32_t bytecode_reloc_offset_u32; | |
200 | const uint32_t insn_len = | |
201 | sizeof(struct load_op) + sizeof(struct get_symbol); | |
202 | ||
203 | insn = calloc(insn_len, 1); | |
204 | if (!insn) { | |
205 | ret = -ENOMEM; | |
206 | goto end; | |
207 | } | |
208 | ||
209 | insn->op = BYTECODE_OP_GET_SYMBOL; | |
210 | ||
211 | /* | |
212 | * Get offset in the reloc portion at which the symbol name | |
213 | * will end up at (GET_SYMBOL's operand points there). | |
214 | */ | |
215 | bytecode_reloc_offset_u32 = bytecode_get_len(&(*bytecode_reloc)->b) + | |
216 | sizeof(reloc_offset); | |
217 | symbol_offset.offset = (uint16_t) bytecode_reloc_offset_u32; | |
218 | memcpy(insn->data, &symbol_offset, sizeof(symbol_offset)); | |
219 | ||
220 | /* | |
221 | * Get offset in the bytecode where the opcode will end up at, | |
222 | * the reloc offset points to it. | |
223 | */ | |
224 | reloc_offset_u32 = bytecode_get_len(&(*bytecode)->b); | |
225 | if (reloc_offset_u32 > LTTNG_FILTER_MAX_LEN - 1) { | |
226 | ret = -EINVAL; | |
227 | goto end; | |
228 | } | |
229 | reloc_offset = (uint16_t) reloc_offset_u32; | |
230 | ||
231 | /* Append op in bytecode. */ | |
232 | ret = bytecode_push(bytecode, insn, 1, insn_len); | |
233 | if (ret) { | |
234 | goto end; | |
235 | } | |
236 | ||
237 | /* Append reloc offset. */ | |
238 | ret = bytecode_push(bytecode_reloc, &reloc_offset, | |
239 | 1, sizeof(reloc_offset)); | |
240 | if (ret) { | |
241 | goto end; | |
242 | } | |
243 | ||
244 | /* Append symbol name. */ | |
245 | ret = bytecode_push(bytecode_reloc, symbol, 1, strlen(symbol) + 1); | |
246 | ||
247 | end: | |
248 | free(insn); | |
249 | return ret; | |
250 | } | |
251 | ||
763f0d4c SM |
252 | /* |
253 | * Allocate an lttng_bytecode object and copy the given original bytecode. | |
254 | * | |
255 | * Return allocated bytecode or NULL on error. | |
256 | */ | |
257 | LTTNG_HIDDEN | |
2b00d462 SM |
258 | struct lttng_bytecode *lttng_bytecode_copy( |
259 | const struct lttng_bytecode *orig_f) | |
763f0d4c | 260 | { |
2b00d462 | 261 | struct lttng_bytecode *bytecode = NULL; |
763f0d4c SM |
262 | |
263 | bytecode = zmalloc(sizeof(*bytecode) + orig_f->len); | |
264 | if (!bytecode) { | |
265 | goto error; | |
266 | } | |
267 | ||
268 | memcpy(bytecode, orig_f, sizeof(*bytecode) + orig_f->len); | |
269 | ||
270 | error: | |
271 | return bytecode; | |
272 | } |